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Finding the Fourth Proportional to 87.29, 120.46 and 57.75

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Solution

The fourth proportional to 87.29, 120.46 and 57.75 is: 79.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.29 : 120.46 = 57.75 : x
  2. Step 2: Convert to fraction form
    87.29/120.46 = 57.75/x
  3. Step 3: Cross multiply
    87.29x = 120.46 × 57.75
  4. Step 4: Simplify right side
    87.29x = 6,957.26
  5. Step 5: Solve for x
    x = 6,957.26/87.29
  6. Step 6: Final answer
    x = 79.70

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.