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Finding the Fourth Proportional to 86.38, 119.16 and 55.30

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Solution

The fourth proportional to 86.38, 119.16 and 55.30 is: 76.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.38 : 119.16 = 55.30 : x
  2. Step 2: Convert to fraction form
    86.38/119.16 = 55.30/x
  3. Step 3: Cross multiply
    86.38x = 119.16 × 55.30
  4. Step 4: Simplify right side
    86.38x = 6,589.55
  5. Step 5: Solve for x
    x = 6,589.55/86.38
  6. Step 6: Final answer
    x = 76.29

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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.