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Finding the Fourth Proportional to 87.51, 131.19 and 53.28

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Solution

The fourth proportional to 87.51, 131.19 and 53.28 is: 79.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.51 : 131.19 = 53.28 : x
  2. Step 2: Convert to fraction form
    87.51/131.19 = 53.28/x
  3. Step 3: Cross multiply
    87.51x = 131.19 × 53.28
  4. Step 4: Simplify right side
    87.51x = 6,989.80
  5. Step 5: Solve for x
    x = 6,989.80/87.51
  6. Step 6: Final answer
    x = 79.87

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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.