1) Set up proportions for the ratios:

Cross multiply the fractions:

Divide both sides by 2 to get x by itself.

5 to 2 is equal to
10 to 4.
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2) Set up proportions for the ratios:

Cross multiply the fractions:

Divide both sides by 21 to get x by itself:

14 to 21 is equal to
10 to 15.
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OPTIONAL:
To make 2) easier to solve, simplify 14 to 21.

Then, continue with the problem as described above:


