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Two related rates problems |
2005-12-29 |
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From Shimaera:
#1. A manufacturer determines that the cost of producing x of an item is C(x)=0.015x2+12x+1000 and the price function is p(x)=250+2x/10. Find the actual and marginal profits when 500 items are produced.
#2. At 9 a.m a car is 10km directly east of Marytown and is traveling north at 100 km/h. At the same time, a truck leaves Marytown traveling east at 70 km/h. At 10 a.m, how is the distance between the car and the truck changing?
Answered by Penny Nom. |
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Joey had 8 drinking glasses, all of different sizes. |
2005-12-29 |
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From Danielle:
Joey had 8 drinking glasses, all of different sizes. he has lined them up from smallest to largest and numbered them #1 (smallest) to #8 (largest). he knows that glass #4 holds 10 ounces and that glass #7 holds a pint, or 16 ounces. Now he wants to figure out how much all the others hold!
He experiments by filling up different glasses with water and pouring the water back and forth into other glasses. Her are his results:
Answered by Penny Nom. |
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An array of pennies by year |
2005-12-29 |
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From Sheila:
What is an array? How do you create an array using 100 pennies by years?
Answered by Penny Nom. |
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Milliliters to grams |
2005-12-29 |
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From Kaitlyn:
If I'm using baking soda, how do I convert milliliters to grams?
Answered by Harley Weston. |
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One car leaves a spot traveling at 100 km per hour |
2005-12-28 |
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From Jason:
One car leaves a spot traveling at 100 km per hour. The second car leaves the same spot 15 minutes later and traveling at 120 km per hour. How long does it take for the second car to catch up to the first car?
Answered by Penny Nom. |
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Twelve golf balls |
2005-12-28 |
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From Todd:
You have 12 golf balls and 11 of them are the exact same weight, but one of them is either a little heavier or a little lighter. You only have three attempts to weigh the balls. How can you determine which ball weighs more/less than the rest?
Answered by Penny Nom. |
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2800 sq meters |
2005-12-27 |
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From Roger:
I am going to buy some land and its 2800 sq meters. Is it a acre?
Answered by Penny. |
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If an acre of land is covered with one inch of water |
2005-12-27 |
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From Patti:
If an acre of land (43560 sq ft) is covered with one inch of water, how many gallons of water cover that acre.
Answered by Penny Nom. |
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A goat is tied to the corner of a 50 ft square outbuilding |
2005-12-24 |
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From Danielle:
Topic: A goat is tied to the corner of a 50 ft square outbuilding with a 40 ft. rope.
a) What is the measure of the partial circumference created as the goat walks at the full length of the rope?
b) Since the goat is trimming the grass from part of the outbuilding, how much of the perimeter of the outbuilding will the building owner have to trim?
Answered by Penny Nom. |
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Why do we bother learning pre-algebra and algebra 1? |
2005-12-23 |
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From Priya:
My students always ask "Why do we bother learning pre-algebra and algebra 1?" and I haven't found an answer to satisfy them yet. Can you help me? My students are from grade 9 to 11. I have tried giving them real life examples in each topic but it just feels like they are not satisfied!!!
Answered by Penny Nom. |
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Cubic yards of fill |
2005-12-23 |
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From Mike:
And I have a question in regards to the amount of fill needed to bring a vacant lot up to "grade level".
The lot is 112' x 87' and I need to bring in fill to elevate the finished level up 4'.
Answered by Penny Nom. |
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Percentages in our daily life |
2005-12-23 |
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From Naina:
what are the uses of percentages in our daily life
Answered by Penny Nom. |
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Two dogs and a flea |
2005-12-23 |
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From Michelle:
Two dogs, each traveling at 10 ft/sec, run toward each other from 500 feet apart. As they run, a flea flies from the nose of one dog to the nose of the other at 25 ft/sec. The flea flies between the dogs in this manner until it is crush when the dogs collide. How far did the flea fly?
Answered by Penny Nom. |
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Cubic metres to cords |
2005-12-22 |
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From Duncan:
I have a quote of $2.95 per cubic metre of roundwood but I need the conversion equation to convert the above to a $ per cord.
Answered by Penny Nom. |
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Mean and average |
2005-12-22 |
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From Jerry:
This is just a question from a degreed engineer that has a "understanding" problem. please go to http://www.metrika.com/3medical/hemoglobin-m.html
At the end of the page they talk about "mean" vrs "average" there does appear to be a difference. What is it?
Answered by Harley Weston. |
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