Finding the Third Proportional to 521 and 638
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Solution
The third proportional to 521 and 638 is: 781.27
Step by Step Solution
- Step 1: Write the proportion equation
521 : 638 = 638 : x - Step 2: Convert to fraction form
521/638 = 638/x - Step 3: Cross multiply
521x = 638 × 638 - Step 4: Simplify right side
521x = 407,044 - Step 5: Solve for x
x = 407,044/521 - Step 6: Final answer
x = 781.27
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Why These Related Problems?
These problems maintain the same ratio (1.22) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.