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Finding the Fourth Proportional to 87.36, 130.24 and 79.68

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Solution

The fourth proportional to 87.36, 130.24 and 79.68 is: 118.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.36 : 130.24 = 79.68 : x
  2. Step 2: Convert to fraction form
    87.36/130.24 = 79.68/x
  3. Step 3: Cross multiply
    87.36x = 130.24 × 79.68
  4. Step 4: Simplify right side
    87.36x = 10,377.52
  5. Step 5: Solve for x
    x = 10,377.52/87.36
  6. Step 6: Final answer
    x = 118.79

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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.