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Finding the Fourth Proportional to 657.20, 985.90 and 397.39

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Solution

The fourth proportional to 657.20, 985.90 and 397.39 is: 596.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.20 : 985.90 = 397.39 : x
  2. Step 2: Convert to fraction form
    657.20/985.90 = 397.39/x
  3. Step 3: Cross multiply
    657.20x = 985.90 × 397.39
  4. Step 4: Simplify right side
    657.20x = 391,783.34
  5. Step 5: Solve for x
    x = 391,783.34/657.20
  6. Step 6: Final answer
    x = 596.14

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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.