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Finding the Fourth Proportional to 42.85, 63.98 and 39.61

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Solution

The fourth proportional to 42.85, 63.98 and 39.61 is: 59.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    42.85 : 63.98 = 39.61 : x
  2. Step 2: Convert to fraction form
    42.85/63.98 = 39.61/x
  3. Step 3: Cross multiply
    42.85x = 63.98 × 39.61
  4. Step 4: Simplify right side
    42.85x = 2,534.25
  5. Step 5: Solve for x
    x = 2,534.25/42.85
  6. Step 6: Final answer
    x = 59.14

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.