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Ratios and proportions

Equivalent ratios: find the missing number

Fill in the missing number to complete the proportion.

1 to = 4 to 20

Write 4 to 20 as a fraction. Then write an equivalent fraction with 1 as the numerator.

$\frac{2}{20}=\frac{4\;\div\;4}{20\;\div\;4}=\frac{1}{5}$

1 to 5 = 4 to 20

Fill in the missing number to complete the proportion.

7 : 10 = : 90