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Finding the Fourth Proportional to 87.17, 130.64 and 43.79

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Solution

The fourth proportional to 87.17, 130.64 and 43.79 is: 65.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.17 : 130.64 = 43.79 : x
  2. Step 2: Convert to fraction form
    87.17/130.64 = 43.79/x
  3. Step 3: Cross multiply
    87.17x = 130.64 × 43.79
  4. Step 4: Simplify right side
    87.17x = 5,721.32
  5. Step 5: Solve for x
    x = 5,721.32/87.17
  6. Step 6: Final answer
    x = 65.63

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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.