Finding the Third Proportional to 128 and 272
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Solution
The third proportional to 128 and 272 is: 578
Step by Step Solution
- Step 1: Write the proportion equation
128 : 272 = 272 : x - Step 2: Convert to fraction form
128/272 = 272/x - Step 3: Cross multiply
128x = 272 × 272 - Step 4: Simplify right side
128x = 73,984 - Step 5: Solve for x
x = 73,984/128 - Step 6: Final answer
x = 578
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These problems maintain the same ratio (2.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.