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Finding the Fourth Proportional to 87.39, 131.08 and 51.55

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Solution

The fourth proportional to 87.39, 131.08 and 51.55 is: 77.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.39 : 131.08 = 51.55 : x
  2. Step 2: Convert to fraction form
    87.39/131.08 = 51.55/x
  3. Step 3: Cross multiply
    87.39x = 131.08 × 51.55
  4. Step 4: Simplify right side
    87.39x = 6,756.52
  5. Step 5: Solve for x
    x = 6,756.52/87.39
  6. Step 6: Final answer
    x = 77.32

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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.