Finding the Third Proportional to 391 and 647
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Solution
The third proportional to 391 and 647 is: 1,070.61
Step by Step Solution
- Step 1: Write the proportion equation
391 : 647 = 647 : x - Step 2: Convert to fraction form
391/647 = 647/x - Step 3: Cross multiply
391x = 647 × 647 - Step 4: Simplify right side
391x = 418,609 - Step 5: Solve for x
x = 418,609/391 - Step 6: Final answer
x = 1,070.61
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These problems maintain the same ratio (1.65) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.