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Finding the Fourth Proportional to 87.79, 131.62 and 42.10

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Solution

The fourth proportional to 87.79, 131.62 and 42.10 is: 63.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.79 : 131.62 = 42.10 : x
  2. Step 2: Convert to fraction form
    87.79/131.62 = 42.10/x
  3. Step 3: Cross multiply
    87.79x = 131.62 × 42.10
  4. Step 4: Simplify right side
    87.79x = 5,541.20
  5. Step 5: Solve for x
    x = 5,541.20/87.79
  6. Step 6: Final answer
    x = 63.12

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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.