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Finding the Fourth Proportional to 100.89, 139.29 and 62.13

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Solution

The fourth proportional to 100.89, 139.29 and 62.13 is: 85.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.89 : 139.29 = 62.13 : x
  2. Step 2: Convert to fraction form
    100.89/139.29 = 62.13/x
  3. Step 3: Cross multiply
    100.89x = 139.29 × 62.13
  4. Step 4: Simplify right side
    100.89x = 8,654.09
  5. Step 5: Solve for x
    x = 8,654.09/100.89
  6. Step 6: Final answer
    x = 85.78

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.