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Finding the Fourth Proportional to 100.60, 138.81 and 59.15

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Solution

The fourth proportional to 100.60, 138.81 and 59.15 is: 81.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.60 : 138.81 = 59.15 : x
  2. Step 2: Convert to fraction form
    100.60/138.81 = 59.15/x
  3. Step 3: Cross multiply
    100.60x = 138.81 × 59.15
  4. Step 4: Simplify right side
    100.60x = 8,209.62
  5. Step 5: Solve for x
    x = 8,209.62/100.60
  6. Step 6: Final answer
    x = 81.61

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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.