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Finding the Fourth Proportional to 86.31, 119.13 and 53.55

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Solution

The fourth proportional to 86.31, 119.13 and 53.55 is: 73.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.31 : 119.13 = 53.55 : x
  2. Step 2: Convert to fraction form
    86.31/119.13 = 53.55/x
  3. Step 3: Cross multiply
    86.31x = 119.13 × 53.55
  4. Step 4: Simplify right side
    86.31x = 6,379.41
  5. Step 5: Solve for x
    x = 6,379.41/86.31
  6. Step 6: Final answer
    x = 73.91

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.