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Finding the Fourth Proportional to 87.45, 120.64 and 50.61

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Solution

The fourth proportional to 87.45, 120.64 and 50.61 is: 69.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.45 : 120.64 = 50.61 : x
  2. Step 2: Convert to fraction form
    87.45/120.64 = 50.61/x
  3. Step 3: Cross multiply
    87.45x = 120.64 × 50.61
  4. Step 4: Simplify right side
    87.45x = 6,105.59
  5. Step 5: Solve for x
    x = 6,105.59/87.45
  6. Step 6: Final answer
    x = 69.82

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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.