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A sulphuric acid solution 2018-07-12
From Tan:
How much 96% h2so4 to add into sulphuric acid 30% in order to make it to 50% sulphuric acid?
Answered by Penny Nom.
A circle inscribed in a regular polygon 2018-07-12
From Naveen:
The radius of inscribed circle for n sided regular polygon of a side a is? Please with proof
Answered by Penny Nom.
The price of a watermelon 2018-07-07
From errin:
the price of the watermelon is directly proportional to its weight. If a watermelon that weighs 22 pounds cost $5.40, how much will a 17.5 pound watermelon cost?
Answered by Penny Nom.
Four odd factors 2018-07-04
From Manchali:
Find a number that has 4 factors and all of them are odd numbers.
Answered by Penny Nom.
The surface area of a levee 2018-07-04
From John:
Figuring out the surface area in sq. Ft. Of a levee

Top of levee width: 6
Width of base (from toe to toe): 40
Length of levee: 1,250

Answered by Penny Nom.
Creating a number sentence 2018-06-29
From trish:
First I have to solve the problem. Then write a number sentence for the problem. The problem: By installing a $120.00 thermostat that reduces the temperature setting at night a family hopes to cut its annual fuel bill for heating oil by 8%, and recover the cost of the thermostat in fuel savings after 2years. What was the family's annual fuel bill before installing the thermostat? Thanks can't figure this one out!
Answered by Penny Nom.
Soil in a raised bed 2018-06-24
From Georgia:
Good Afternoon,

I'm planning on building a raised bed garden measuring 6 feet long x 4 feet wide x 12 inches deep. I'm not sure how to calculate the amount of soil to fill it up. I will have to purchase the soil in 2 cubic feet bags.

I've read several articles about this topic on various gardening websites, and one of them stated it would take a ton of soil to fill up an 8 foot long x 4 foot wide x 12 inch deep raised bed garden.

I'd greatly appreciate it if you could help me out with this quandary.

Thank you for your prompt and courteous response.

Kind Regards,

Answered by Penny Nom.
Three consecutive whole numbers 2018-06-22
From whaha:
the sum of three consecutive whole numbers divided by 4 is equal to 6. find the numbers.
Answered by Penny Nom.
The product of two numbers 2018-06-19
From amie:
the product of two numbers is 108.when the larger number is divided by the smaller number the quotient is 3. What are the number.tnx
Answered by Penny Nom.
The domain of f(g(x)) 2018-06-18
From Joshua:
What are the restrictions of the domain of f(g(x))?
Answered by Penny Nom.
A question about the empty set 2018-06-17
From Andrey:
Hello there!
I got that an empty set is a subset of every set.
There is a question.
Is an empty set an element of every set?
∅ ⊆ {x}True
∅ ∈{x}?
Sorry if the question is easy. A set theory is a bit confusing.

Answered by Penny Nom.
The number of terms in an arithmetic sequence 2018-06-15
From Don:
how many terms in arithmetic sequence are there if the first term and the last term are 3&59 respectively in common difference is 4?
Answered by Harley Weston.
The base for a circular pool 2018-06-10
From Adam:
How many sheet of 4ft by 8ft foam would I need to lay under a pool 15dt in diameter
Answered by Penny Nom.
A tangent to a circle 2018-06-10
From Bellle:
Determine the equation of the circle which has its center at (3,1) and tangent 3x-4y+5=0
Answered by Penny Nom.
The inverse square law 2018-06-05
From Amy:

Question about inverse square law ;

Hi, I'm trying to understand some nuances about this law and
have been reading about it a lot online and trying out some homework
for personal interest (hobby ) - not school related.

I understand that the simple formula is ; 1/d^2

I was wondering about what appears to be an oddity to me, that
I came across when I was working with a test example I found at this
link ;


The problem that caught my interest was this one on that page ;

"1) If a bright flashlight has a light intensity of 15.0 candela at a distance 1.00 m from the lens, what is the intensity of the flashlight 100.0 m from the lens?"

So I have a few different questions about this, but the most important
one is, what does it mean if we replace the "1" in ; 1/d^2 with a different value such as a ratio in the form of a decimal value, so instead we have something like this ;



Does this ratio represent a curve then?

I am thinking that the "1" in the normal formula represents a straight line

Some of the links I was researching ;




Answered by Penny Nom.



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