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Finding the Fourth Proportional to 87.08, 130.01 and 78.17

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Solution

The fourth proportional to 87.08, 130.01 and 78.17 is: 116.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.08 : 130.01 = 78.17 : x
  2. Step 2: Convert to fraction form
    87.08/130.01 = 78.17/x
  3. Step 3: Cross multiply
    87.08x = 130.01 × 78.17
  4. Step 4: Simplify right side
    87.08x = 10,161.84
  5. Step 5: Solve for x
    x = 10,161.84/87.08
  6. Step 6: Final answer
    x = 116.70

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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.