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Finding the Fourth Proportional to 87.10, 120.09 and 75.99

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Solution

The fourth proportional to 87.10, 120.09 and 75.99 is: 104.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.10 : 120.09 = 75.99 : x
  2. Step 2: Convert to fraction form
    87.10/120.09 = 75.99/x
  3. Step 3: Cross multiply
    87.10x = 120.09 × 75.99
  4. Step 4: Simplify right side
    87.10x = 9,125.64
  5. Step 5: Solve for x
    x = 9,125.64/87.10
  6. Step 6: Final answer
    x = 104.77

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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.