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Finding the Fourth Proportional to 657.76, 987.10 and 426.56

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Solution

The fourth proportional to 657.76, 987.10 and 426.56 is: 640.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.76 : 987.10 = 426.56 : x
  2. Step 2: Convert to fraction form
    657.76/987.10 = 426.56/x
  3. Step 3: Cross multiply
    657.76x = 987.10 × 426.56
  4. Step 4: Simplify right side
    657.76x = 421,057.38
  5. Step 5: Solve for x
    x = 421,057.38/657.76
  6. Step 6: Final answer
    x = 640.14

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.