<PRE><B>Question 474879</B>
room measures 13 feet long by 12 feet wide by 8 feet high.
carpet costs $30 a square yard.
paint costs $25 a gallon which covers 300 square feet.
you are painting all 4 walls and the ceiling.
you will need an additional 15% of carpet to account for cutting and waste.
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we&#39;ll do the painting first.
the total square feet that you have to paint is:
13 * 8 * 2 plus 12 * 8 * 2 + 13 * 12 * 1 = 208 + 192 + 156 = 556 square feet.
since a gallon of paint covers 300 square feet, you will need 1.853333333 gallons of paint which rounds up to 2 gallons of paint.
since paint costs $25 a gallon, you will need to pay $50.00 for paint.
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we&#39;ll do the carpeting next.
since carpeting is bought per square yard, you will need to convert square feet to square yards at some point in time.
note that 1 square yard is equal to 3 feet * 3 feet which is equal to 9 square feet.
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if your answer is in square feet, you divide by 9 to get square yards.
if your answer is in square yards, you multiply by 9 to get square feet.
for example:
9 square yards is equal to 9*9 = 81 square feet.
that would mean that 9 feet by 9 feet = 81 square feet.
divide feet by 3 to get yards and that becomes:
3 yards * 3 yards = 9 square yards.
9 square yards * 9 = 81 square feet.
81 square feet / 9 = 9 square yards.
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back to your problem.
your floor is 13 feet by 12 feet.
that would be equal to 156 square feet.
add 15% to get 156 square feet plus 23.4 square feet = 179.4 square feet.
convert that to square yards and you get 179.4 / 9 = 19.933333333 square yards.
assuming that you can only buy carpet by the square yard, that means you have to order 20 square yards.
20 square yards at a price of $30 per square yard is equal to $600.
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you paid a total of $50.00 for the paint and a total of $600.00 for the carpet.
your total bill comes out to $650.00.
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you are close so i suspect you did it right.
the actual answer depends on how you view the problem.
if you don&#39;t round up to the next integer, you will get a different answer than if you do round up to the next integer.
my assumptions were based on what i believed was the units of sale that you were allowed.
you clearly can&#39;t buy partial gallons.
you might be able to buy carpet by the square foot rather than the square yard.
it depends on your interpretation.
hopefully your instructor understand that, and/or has given you specific instructions on how to handle those issues.
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looking at what you did:
your calculations on the carpet look correct, except for the rounding.
if you got $50 on the paint, then your answer would have been 598 + 50 = 648.
where did you get 648.5?
calculation of painting should have been:
13 * 8 * 2 covers 2 walls with a length of 13 and a height of 8.
12 * 8 * 2 covers 2 walls with a length of 12 and a height of 8.
13 * 12 covers 1 ceiling with a length of 13 and a width of 12.
total square feet is equal to 208 + 192 + 156 = 556 square feet.
556/300 = 1.85333333 gallons.
without rounding, this be equal to 46.3333333 dollars.
with rounding, this would be equal to 50 dollars.
598 + 46.3333333 = 644.3333333
598 + 50 = 648
i don&#39;t get 648.5 either way.
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