Finding the Third Proportional to 128 and 142
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Solution
The third proportional to 128 and 142 is: 157.53
Step by Step Solution
- Step 1: Write the proportion equation
128 : 142 = 142 : x - Step 2: Convert to fraction form
128/142 = 142/x - Step 3: Cross multiply
128x = 142 × 142 - Step 4: Simplify right side
128x = 20,164 - Step 5: Solve for x
x = 20,164/128 - Step 6: Final answer
x = 157.53
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These problems maintain the same ratio (1.11) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.