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Finding the Fourth Proportional to 87.75, 132.13 and 78.17

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Solution

The fourth proportional to 87.75, 132.13 and 78.17 is: 117.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.75 : 132.13 = 78.17 : x
  2. Step 2: Convert to fraction form
    87.75/132.13 = 78.17/x
  3. Step 3: Cross multiply
    87.75x = 132.13 × 78.17
  4. Step 4: Simplify right side
    87.75x = 10,328.04
  5. Step 5: Solve for x
    x = 10,328.04/87.75
  6. Step 6: Final answer
    x = 117.70

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.