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Finding the Fourth Proportional to 87.28, 130.84 and 72.16

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Solution

The fourth proportional to 87.28, 130.84 and 72.16 is: 108.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.28 : 130.84 = 72.16 : x
  2. Step 2: Convert to fraction form
    87.28/130.84 = 72.16/x
  3. Step 3: Cross multiply
    87.28x = 130.84 × 72.16
  4. Step 4: Simplify right side
    87.28x = 9,441.41
  5. Step 5: Solve for x
    x = 9,441.41/87.28
  6. Step 6: Final answer
    x = 108.17

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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.