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Finding the Fourth Proportional to 63.30, 87.32 and 39.66

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Solution

The fourth proportional to 63.30, 87.32 and 39.66 is: 54.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    63.30 : 87.32 = 39.66 : x
  2. Step 2: Convert to fraction form
    63.30/87.32 = 39.66/x
  3. Step 3: Cross multiply
    63.30x = 87.32 × 39.66
  4. Step 4: Simplify right side
    63.30x = 3,462.91
  5. Step 5: Solve for x
    x = 3,462.91/63.30
  6. Step 6: Final answer
    x = 54.71

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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.