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Finding the Fourth Proportional to 87.52, 120.54 and 65.65

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Solution

The fourth proportional to 87.52, 120.54 and 65.65 is: 90.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.52 : 120.54 = 65.65 : x
  2. Step 2: Convert to fraction form
    87.52/120.54 = 65.65/x
  3. Step 3: Cross multiply
    87.52x = 120.54 × 65.65
  4. Step 4: Simplify right side
    87.52x = 7,913.45
  5. Step 5: Solve for x
    x = 7,913.45/87.52
  6. Step 6: Final answer
    x = 90.42

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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.