Finding the Third Proportional to 257 and 687
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Solution
The third proportional to 257 and 687 is: 1,836.46
Step by Step Solution
- Step 1: Write the proportion equation
257 : 687 = 687 : x - Step 2: Convert to fraction form
257/687 = 687/x - Step 3: Cross multiply
257x = 687 × 687 - Step 4: Simplify right side
257x = 471,969 - Step 5: Solve for x
x = 471,969/257 - Step 6: Final answer
x = 1,836.46
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Why These Related Problems?
These problems maintain the same ratio (2.67) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.