SOLUTION: If necessary round to nearest hundredth a, it takes 44 pounds of seed to completely plant a 5 acre field. How many acres can be planted per pound of seed? b A color printer p

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Question 92006: If necessary round to nearest hundredth
a, it takes 44 pounds of seed to completely plant a 5 acre field. How many acres can be planted per pound of seed?
b A color printer prints 41 pages in 12 minutes. How many pages does it print per minute

Answer by bucky(2189) About Me  (Show Source):
You can put this solution on YOUR website!
Each of these two problems can be handled as a proportion and proportions can be converted
to the form of an equation by cross-multiplying ... multiplying the numerator on one side by
the denominator on the other side of the proportion. Let's use this process on the two problems
you listed.
.
In the first problem you can say that 44 pounds is to 5 acres as 1 pound is to x acres.
.
In proportion form this is:
.
%2844+lbs%29%2F%285+acres%29+=+%281+lb%29%2F%28x+acres%29
.
Notice that we have lbs in both numerators and acres in both denominators. That's a
good check to make sure we set it up correctly.
.
Now we can cross multiply. Multiply the 44 (a numerator) times x (the denominator
on the other side) and set that product equal to 1 (a numerator) times 5 (the denominator
on the other side). In equation form this is:
.
44+%2A+x+=+1+%2A+5
.
This simplifies to:
.
44x+=+5
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Solve for x by dividing both sides of this equation by 44 to get:
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x+=+5%2F44
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and use a calculator to determine that 5 divided by 44 is 0.1136 which rounds to the nearest
hundredth as 0.11 acres.
.
For your second problem, the printer output is 41 pages in 12 minutes and this is proportional
to an unknown number of pages (call it x) in 1 minute. In proportion form this can be
written as:
.
%2841+pgs%29%2F%2812+mins%29+=+%28x+pgs%29%2F%281+min%29
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Both of the numerators are in terms of pages and both of the denominators are in terms of
minutes. That checks. By cross multiplying this becomes:
.
41%2A1+=+12%2Ax
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which simplifies to:
.
12x+=+41
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Solve for x by dividing both sides by 12 to get:
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x+=+41%2F12+=+3.41666
.
So in one minute the printer puts out 3.4166 pages which to the nearest hundredth is
3.42 pages.
.
Hope this helps you to understand the problem and how proportions can be used to solve problems
such as these.