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The original cost when you only know a percentage 2018-11-13
From john:
I was wonder how to find the Original cost when you don't know original cost

The amount paid was 13.82 that is suppose to represent 20% because Insurance pays 80% Thank You

Answered by Penny Nom.
Fixed cost 2018-09-13
From Heather:
On the bus question you answered, what would be the fixed rate? Is that the rate per person or is that also the base rate? ( cost of empty bus)?
Answered by Penny Nom.
The wholesale price given the retail price and the markup 2018-02-07
From Matthew:
Retail $99
Mark-up is 80%

What is the equation to find the original (wholesale) price (55)?


Answered by Penny Nom.
Selling price and markup 2017-04-24
From Julie:
What would the cost of an item be, if the sell price was $50 and the markup 48%
Answered by Penny Nom.
The cost of a piece of sheet metal 2017-04-14
From Mohammed:
I bought a 2 mm sheet plate of 1.2m 2.4m in fijian $95. I used 1.95m 0.4m from that sheet plate. What will be my total cost for the sheet plate I used. It was a mild steel plate.
Answered by Penny Nom.
Profit 2016-06-15
From Toyia:
12.87 profit from 21.99 sale. What is the percentage that was taken off the 21.99
Answered by Penny Nom.
The original price before a discount and taxes 2015-12-09
From Michelle:
Good day,

I would like to know if there is a particular equation to validate the following information:

I had to find the original cost of an item sold for 759.36$ before a 25% discount and 13% taxes. I know we must use separate question to obtain the answer but I am unsure how to write the equation to validate my answer.

Answered by Penny Nom.
The amount before profit and overhead 2015-06-12
From kelly:
I have an existing amount of $22,750.00. this includes the profit at 10% and overhead at 10%. How do I remove the profit and overhead in order to come up with the original starting figure?
Answered by Penny Nom.
A word problem 2015-05-08
A businessman bought a number of similar articles for a total of sh. 6000. Three of the articles turned out to be defective with no resale value. He sold the remaining articles at 12.5% each above the cost price making a total profit of sh 480. How many articles had he bought?
Answered by Penny Nom.
What is our cost? 2015-01-27
From Johanna:
I have a pieces of 3/4" sch40 (round tube) 240" long at $70. What is our cost. We also add 35% to our cost for selling price. How do I figure this out?
Answered by Penny Nom.
A piecewise graph 2014-05-10
From Zoe:
Lightning Energy charges residential users for each unit of electrical energy bought from them each quarter, according to the scale below:
0-500 units cost 17 cents per unit
500-1500 units cost $85 plus 10 cents for each unit in the excess of 500
1500 or more units cost $185 plus 9 cents for each unit in excess of 1500
Sketch a graph showing the charge C as a function of U for up to 2000 electricity units

Answered by Penny Nom.
Converting cost per cubic yard to cost per ton 2014-02-05
From Mayra:
If 18 cubic yards= 25 tons and it's $28.00 per yard how much is it a ton. I need help please a refresher on my algebra. Thank you
Answered by Penny Nom.
If I know only the tax amount, how do I figure out total cost? 2013-08-11
From Patric:
If I know only the tax amount, how do I figure out total cost?
Answered by Penny Nom.
Your profit should be 20% of your cost 2013-02-21
From anis:
if the customer says your profit should be 20% of your cost..

1) my selling value should be cost +20% of cost = SP


2)cost / 0.80 = SP which is correct...if the second answer is right how should i justify my customer

Answered by Penny Nom.
Painting a pool 2012-03-25
From Salai:
A swimming pool measures 8m long, 6m wide and 1.5 m deep. The special paint for the pool cost $6per square metre. How much will it cost to paint the interior surfaces of the pool ?
Answered by Penny Nom.
What was the cost price of the article? 2011-11-10
From tashana:
By selling an article for $320,the profit was 20% of the cost price.what was the cost price of the article.
Answered by Penny Nom.
The cost of petrol 2011-08-26
From Sam:
Hi, i'm confused about this question from my textbook, here goes: The cost of petrol for a 240 km journey for a car which runs 12 km on each litre of petrol is $24. What would be the cost of petrol for a 500 km journey for a van which runs 11km on each litre of petrol? please answer in detail and thanks in advance :)
Answered by Penny Nom.
Administration costs and profit 2011-04-05
From brian:
Hi , If I have direct job costs of $100. and my administration is 20 % and I want to make a 15 % profit , how would I calculate the administration and profit and what would be the total of each be and also the final total?


Answered by Penny Nom.
I need to make $1000 profit 2011-03-28
From Kat:
I need to make $1000 profit selling plants for $3 each. My direct cost is $2 per plant and my overhead is $5oo. How many pots (plants = 1 per pot) do I need to make $1000?
Answered by Penny Nom.
How much per ft. does it cost? 2011-03-14
From Linda:
350 lbs. of coil at $1.80 per lb equals $630. each coil is 780 ft. how much per ft. does it cost?
Answered by Penny Nom.
The markup rate is 40% of the cost 2011-03-14
From Abeth:
A wallet sells for 450 pesos. the markup rate is 40% of the cost. find the cost of the wallet and markup.
Answered by Penny Nom.
Cost of a driveway 2010-10-11
From arlene:
What is the total cost of a driveway that is 25' wide and 45' long with 4" thickness if the concreat cost 92.00 per cubic yard and labor is 70.00 a cubic yard?
Answered by Stephen La Rocque.
Selling price, cost and profit 2010-06-22
From Alex:
The profit on a certain television set is 16.5% of the cost price. If the profit is $330, Find:
a) the cost price
b)the selling price of the television

Answered by Penny Nom.
Frank makes picture frames 2010-02-20
From Carol:
Frank makes picture frames his revenue from sales is R=$13.60x for frames sold. The cost making frames is C=$5.80x+$120 for frames made. What is the minum number of frames Frank must make and sell in order for his revenue to be greater than his costs.
Answered by Penny Nom and Melanie Tyrer.
Ordering pizza for 162 people 2009-10-01
From Jean:
Need to know how to feed about 162 people 70 square inches of pizza at the lowest price.

22" Pizza is $9.95
16" Pizza is $5.25
12" Pizza is $2.99

Answered by Penny Nom.
Maximum profit 2009-05-11
From Sally:
a manufacturer of dresses charges $90 per dress up to 100 units and the average production cost is $60 per dress. to encourage larger orders the company will drop the price per dress by .10 for orders in excess of 100. I need to find the largest order the company should allow with the special discount to realize maximum profit.
Answered by Harley Weston.
A T-shirt fundraiser 2009-01-11
From Andre:
Lou's class is selling T-shirts for a fundraiser. The supplier charges 750$ for the initial design and the set-up plus 5$ for each imprinted shirt. The students sell the shirts for 15$ each.
a)How many T-shirts do the students need to sell to break even?
b)How much profit will the students make if they sell 150 shirts?

Answered by Harley Weston.
30% profit 2009-01-06
From bob:
this is a basic question that I just can't get thru my head.

I know all my cost for a product, if I want to sell at a given profit can I divide by a given number, example for 30 % divide by .7 or do I multiply? Is there a simple answer for this? Sure would make my work a lot easier.

Thank you for your time

Puzzled in Ohio

Answered by Penny Nom.
The cost of a foundation 2008-12-08
From carl:
Hi, I need to work out the cost of a foundation.

The foundation is 1m deep x 500mm wide and is 6.3 meters long.

The cost per cubic meter for concrete is 1000 rand escuvation of earth will be 100 rand per cubic meter and back filling wil also be 100 rand per cubic meter.

What will the cost be

Answered by Harley Weston.
The cost of a steel plate 2008-11-05
From Tammie:
What is the formula to calculate the following:

I have a plate of steel that is 1/4" x 48" x 192" at a price of $15.23 per square foot What is the formula to calculate the cost if I only use 1/4" x 47-1/4" x 68-1/8" of that steel plate?

Answered by Penny Nom.
How much does Luc pay for his tools?? 2008-10-20
From imran:
Luc makes $1 profit on each tool he sells. Marc makes a $2 profit while paying $5 less for his tools than Luc. Marc thus makes $6 more profit for every $100 invested. How much does Luc pay for his tools??
Answered by Penny Nom.
The selling price 2008-09-04
From Robert:
Client wants to sell his property providing he is left with 100000.00$ net. How do I calculate selling price if commission is 6% and taxes on the commission 6% Fed and 7.5%prov. I'm taking the real estate class and this one really got me.
Answered by Penny Nom.
How many presses should be used? 2008-05-04
From Sarah:
Hi! I am in Calculus and this problem is on my study guide and i just cant figure it out!? A printing company had eight presses, each of which can print 300 copies per hour. It costs $5.00 to set up each press for a run and 12.5+6n dollars to run n presses for an hour. How many presses should be used to print 6000 copies most profitably? Let h equal the number of hours used to print the 6000 copies.
Answered by Harley Weston.
Cost per square metre 2008-03-31
From sandy:
if something measures 7m x 3.6m with a depth of 1 - 1.5m and the total cost is 52 500.00, what is the cost per square metre
Answered by Penny Nom.
The profit was what percent of the cost? 2008-02-29
From sierra:
The profit was what percent of the cost?
Here is some more of that whole problem.
Selling Price-$26.60
Sale Price after the Discount-$19.95
The Profit-$5.95

Answered by Penny Nom.
The cost before tax and shipping 2008-02-06
From jonathan:
Please explain how to solve this problem. I know you have to work backwards. If i have $125 to spend, how do I know the most I can spend before adding 6% tax and 9% shipping.(shipping is cost before tax) I can only figure this out by trial and error. I know there is a better way
Answered by Penny Nom.
Tiles on a basement floor 2008-01-31
I have a basement 1000 sq ft I want to purchase tile that are 18x18inches and they are charging 4.15 sq ft how much would it cost since I will need less tiles to cover the area since it's not 12X12
Answered by Penny Nom.
How many houses must they paint? 2007-12-12
From Natalie:
The question is: Four boys work together,painting houses for the summer.For each house they paint they get 256 pounds. If they work for four months of the summer and their expenses are 152 pounds per a month, how many houses must they paint for each of them to have one thousand pounds at the end of the summer?
Answered by Penny Nom.
What would be the cost of a 10 in * 15 in canvas? 2007-12-01
From Jasmine:
a 40in *60 in canvas is sold for $60.00 if the price is determined by the cost of the material what would be the cost of a 10 in * 15 in canvas
Answered by Stephen La Rocque.
Maximizing profits II 2007-10-05
From a student:
Suppose there are three firms with the same demand function. The function is Q=1000-40P. Each firm also a a cost function.
Firm 1: 4000+5Q, Firm 2: 3000+5Q, Firm 3: 3000+7Q.
What price should each firm charge if it wants to maximize profits.

Answered by Harley Weston.
Breaking even 2007-08-16
From virginia:
a company that manufactures bikes has a fixed cost of $100,000.00 it costs $100 to produce each bike. the selling price per bike is $300.00

write the cost function, c
write the revenue function, r
determine the break even point

Answered by Leeanne Boehm and Steve La Rocque.
The cost of some groceries 2007-07-18
From A student:
Two boxesof the cereal and our four cans of the pears were boutht at grocery store,the cereal cost $2.29per box and the pears cost 79cent per can.sales tax is 6% what was the total cost of the food diregerding ?
Answered by Penny Nom.
The cost of laying cable 2007-06-05
From Gilligan:
MetroMedia cable is asked to provide service to a customer whose house is located 2 miles from the road along which the cable is buried. The nearest connection box for the cable is located 5 miles down the road. If the installation cost is 10 dollars per mile along the road and 14 dollars per miles off the road, express the total cost C of installation as a function of the distance x (in miles) from the connection box to the point where the cable installation turns off the road. Give the domain. Also, compute the cost if x = 1 mile and if x = 3 miles. In order to use the given values for x, do I need a formula? If so, what is that formula? I can take it from there.
Answered by Stephen La Rocque.
If I know the total is 15% over cost, what is the cost? 2007-05-18
From Theresa:
I have a job that is $25,250 total to complete the job. The customer asked how much am I charging. I told him I was charging 15% over the Cost. What is the formula to calculate the cost of the job?
Answered by Stephen La Rocque.
Cost of ribbon 2007-03-20
From kelly:
we are doing rate Ribbon costs $1.44 for 3m a). What is the cost per meter? b). How much would 5 m of ribbon cost? c). How much ribbon could you buy for $12.00
Answered by Penny Nom.
Cost per square foot 2007-02-14
From llinden:
how do you figure out the cost of square footage? the amount per sq ft is $28 Thank you
Answered by Gabriel Potter.
What is the total cost of a driveway ... 2006-08-29
From Ismael:
What is the total cost of a driveway 15' wide, 40' long and 4" thick if the concrete costs $60.00 per cubic yard and the labor costs $1.25 per square foot?
Answered by Stephen La Rocque.
Minimizing a cost 2006-07-25
From Edward:
The cost of running a car at an average speed of V km/h is given by c= 100 + (V2 / 75) cents per hour. Find the average speed (to the nearest km/h) at which the cost of a 1000 km trip is a minimum.
Answered by Stephen La Rocque.
54x14x8 at $28.00 per cubic foot 2006-07-24
From Toi:
How much would it cost if I had an item that was 54x14x8 and it was $28.00 per cubic foot?
Answered by Stephen La Rocque.
Tiling a floor 2006-06-08
From Marguerite:
A builder is adding a 20' X 28' addition to a house. He has two choices: he can use 8" X 8" tile @ $.98 a tile or 12" X 12" tile @ $1.98 a tile. How much money would he save by using the least expensive choice?
Answered by Stephen La Rocque and Penny Nom.
Can you explain the differences between margin and mark up? 2006-06-07
From Michelle:

I have a widget I buy for $10. I want to make a 40% margin on the product cost. What do I then sell to the customer for?

Also, can you explain the differences between margin and mark up?

Answered by Penny Nom.
What is the original cost? 2006-04-19
From Charlie:
Selling a piece of furniture for $670 and the profit is 35%. What is the original cost?
Answered by Stephen La Rocque.
What is the cost price? 2006-04-14
From Purushotham:
If the selling price is 120 and the profit is 20%, what is the cost price?
Answered by Stephen La Rocque.
The cost of pizza 2006-03-28
From Kristine:
Use the formula for the area of a circle, A=3.14rsq, to determine which is a better deal: a 14-in. pizza for $10.50 or a 16-in. pizza for $11.95. Using 3.14 for pi
Answered by Penny Nom.
Adding a cellar 2006-03-14
From Spencer:

You want to add a cellar to your store. The construction company told you it would cost $5.90 per cubic yard to dig the cellar plus $20.00 per square ft. to finish it.

How much will it cost to add a cellar 36 feet long, 14 feet wide, and 8 feet deep?

Answered by Stephen La Rocque.
Profit 2006-02-25
From Vernessa:
ABC company wants to sell enough products to earn a profit of $40,000, if unit sales are $10 and variable costs $8 , fixed cost $80,000 how many units must be sold to earn a profit of $40,000.
Answered by Penny Nom.
Brochure cost 2005-11-02
From Duk:
The organizers of the walkathon want to have brochures printed to advertise the event. They get cost estimates from two printing companies. The costs are given by the equations.

Company A : C= 15 + 0.10n
Company B : C= 0.25n

For what number of brochures is the cost the same for both companies?

Answered by Penny Nom.
Marked down 31% 2005-10-27
From Virginia:

Question: How do you calculate a percentage back into a cost?

Example: $1,025.00 sale cost and I want to add 31 percent back into it for a list cost.

Answered by Penny Nom.
Painter's caps 2005-10-19
From Duk:
The equation C=10 +2n represents the cost in dollars, C, for n painter's caps advertising the walkathon. Which pair of values could represent a number of caps and the cost for that number of caps, (n, C)?

(0, 10) (7, 24) (15, 30)

Answered by Penny Nom.
Cost price 2005-05-25
From Sunitha:
What is (how to calculate) the cost price of a product which is marked-up by 15% and retailed at $25?
Answered by Penny Nom.
The cost of concrete 2005-03-08
From Cathy:
Compute the cost of ready mixed concrete for a driveway 70ft long, 10ft wide, 3 inches deep at a cost of $30.00 per cubic yard
Answered by Penny.
Some ratio problems 2004-03-13
From Hossen:

1) After James spent 2/5 of his pocket money on magazines, and 1/4 of his pocket money at a football match, he had 1.75 left. How much pcket money did he have in the beginning?

2) A joint of Lamb costs 5.95 per/kg. The price per kilogram is reduced. A joint weighing 1.2kg is reduced by 50p.

A) What is the reduced price per kilogram?


Answered by Penny Nom.
Room and board fees 2003-11-29
From Jennifer:
A certain university wishes to determine room and board fees for the next academic year. For the current year, the fee is $3600 per student and 1800 students are living in the residence halls. Past data suggests that for every $300 increase in the semester fee, 200 fewer students will choose to live in the dorms. There are also costs to the university associated with the residence halls. The fixed costs total $2,000,000 per semester. the variable costs are currently $1000 per student but will fall $100 per student for each decrease of 100 students. Your task is to help the university determine the optimal fee. Assume linear relationships between the number of students and the fee and between the number of students and the cost per student
Answered by Penny Nom.
Which is the better buy? 2002-12-04
From Lynda:
my question is the big can held 18 ouces and cost $2.52.The small can held only 12 ounces and cost $1.08. Find both unit prices. which can was better buy?
Answered by Penny Nom.
Sodding the yard 2002-04-08
From Craig:
my parents want to lay sod in our back yard.

the sod cost $2.00 per square foot.

The size of our yard is 20x20 and 26x41

Answered by Penny Nom.
A phone bill 2001-06-18
From Janet:
What is the formuala to calculate cost per minute?

Here is the data below

# of calls - 238
# of minutes - 443
cost - $70.06

Answered by Penny Nom.
Maximize profit 2001-05-09
From Brian:
The marginal cost for a certain product is given by MC = 6x+60 and the fixed costs are $100. The marginal revenue is given by MR = 180-2x. Find the level of production that will maximize profit and find the profit or loss at that level.
Answered by Harley Weston.
Delivering firwood 2001-02-20
From Jackie:
Two college students earn extra money on weekends by delivering firwood in thier pickup truck. They have found that they can sell x cords per weekend at a price of p dollars per cord, where x=75-3/5 p. The students buy the firewood from a supplier who charges them C dollars for x cords to the equation C=500+15 x+1/5 x2.

a) find a function f such that P=f(p), where P dollars is the profit per weekend for the students if they charge p dollars per cord.

b)find the profit P dollars if p=$95

Answered by Penny Nom.
Staying under budget. 1999-06-22
From Chris:
If I had $147.69 and I had to buy 200 bannas at $.46 & 100 potatos at $.42 each how do I stay under my buget
Answered by Penny Nom.



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