Problem
Each member of a research group visited either the Virgin Islands or Hawaii...
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So What?
Math questions involving two equations and two unknowns can usually be combined into one equation with one unknown.
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SAT: Grid-In Question #2 |
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Question:
If the ratio of 300 to c is equal to the ratio of 2 to 1, and the ratio of c to n is equal to the ratio of 2 to 3, what is the value of n - c?
| Take this problem one step at a time. You know that the ratio of |
| 300 |
to |
c |
is equal to the ratio of 2 to 1, so set up an equation and |
| solve for |
c |
. You should have |
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300 |
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 |
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c |
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= |
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2 |
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1 |
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. |
| Cross-multiplying, you get |
300 |
= |
2 |
c |
, and dividing both sides by |
| Now set up an equation for the second proportion. If the ratio of |
| c |
to |
n |
is equal to the ratio of 2 to 3, then |
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c |
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n |
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= |
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2 |
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3 |
|
|
. You know the |
| value of |
c |
, so plug it in and solve for |
n |
. This yields |
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150 |
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n |
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= |
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2 |
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3 |
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. |
| Cross-multiplying gives you |
450 |
= |
2 |
n |
. Dividing both sides by 2, |
| Remember that the problem asks for the value of |
n |
- |
c |
, which is |
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