### Start Learning Now

Our free lessons will get you started (Flash® 10 required).

### Solving Proportions

• Portion: An equality of two ratios

## Find two equivalent ratios for each [3/5]

• [(3 ×2)/(5 ×2)] = [6/10]
• [(6 ×2)/(10 ×2)] = [12/20]

## Find two equivalent ratios for each [11/44]

• [(11 ÷11)/(44 ÷11)] = [1/4]
• [(1 ×2)/(4 ×2)] = [2/8]

## Use mental math to solve the proportion [3/5] = [x/10]

• [(3 ·2)/(5 ·2)] = [x/10]

## Use mental math to solve the proportion [1/8] = [x/24]

• [(1 ·3)/(8 ·3)] = [x/24]

## Use mental math to solve the proportion [3/z] = [12/16]

• [(3 ·4)/(z ·4)] = [12/16]

## Tell whether the two ratios form a proportion [4/40],[8/80]

• [(4 ×2)/(40 ×2)] = [8/40]

## Tell whether the two ratios form a proportion [12/24],[24/47]

• [(12 ×2)/(24 ×2)] = [24/48]

## Tell whether the two ratios form a proportion [13/26],[25/52]

• [(13 ×2)/(26 ×2)] = [26/52]
• [26/52] ≠ [25/52]

## Solve the proportion [5/x] = [2/20]

• 2x = 5 ·20
• 2x = 100
• [2x/2] = [100/2]
• x = [100/2]

## Solve the proportion [2/4] = [y/16]

• 4y = 2 ·16
• 4y = 32
• [4y/4] = [32/4]
• y = [32/4]

### y = 8

*These practice questions are only helpful when you work on them offline on a piece of paper and then use the solution steps function to check your answer.