Finding the Third Proportional to 391 and 500
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Solution
The third proportional to 391 and 500 is: 639.39
Step by Step Solution
- Step 1: Write the proportion equation
391 : 500 = 500 : x - Step 2: Convert to fraction form
391/500 = 500/x - Step 3: Cross multiply
391x = 500 × 500 - Step 4: Simplify right side
391x = 250,000 - Step 5: Solve for x
x = 250,000/391 - Step 6: Final answer
x = 639.39
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These problems maintain the same ratio (1.28) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.