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Finding the Fourth Proportional to 86.29, 129.43 and 71.02

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Solution

The fourth proportional to 86.29, 129.43 and 71.02 is: 106.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.29 : 129.43 = 71.02 : x
  2. Step 2: Convert to fraction form
    86.29/129.43 = 71.02/x
  3. Step 3: Cross multiply
    86.29x = 129.43 × 71.02
  4. Step 4: Simplify right side
    86.29x = 9,192.53
  5. Step 5: Solve for x
    x = 9,192.53/86.29
  6. Step 6: Final answer
    x = 106.53

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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.