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Finding the Fourth Proportional to 87.16, 131.08 and 79.30

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Solution

The fourth proportional to 87.16, 131.08 and 79.30 is: 119.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.16 : 131.08 = 79.30 : x
  2. Step 2: Convert to fraction form
    87.16/131.08 = 79.30/x
  3. Step 3: Cross multiply
    87.16x = 131.08 × 79.30
  4. Step 4: Simplify right side
    87.16x = 10,394.64
  5. Step 5: Solve for x
    x = 10,394.64/87.16
  6. Step 6: Final answer
    x = 119.26

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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.