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Finding the Fourth Proportional to 63.31, 87.40 and 38.75

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Solution

The fourth proportional to 63.31, 87.40 and 38.75 is: 53.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    63.31 : 87.40 = 38.75 : x
  2. Step 2: Convert to fraction form
    63.31/87.40 = 38.75/x
  3. Step 3: Cross multiply
    63.31x = 87.40 × 38.75
  4. Step 4: Simplify right side
    63.31x = 3,386.75
  5. Step 5: Solve for x
    x = 3,386.75/63.31
  6. Step 6: Final answer
    x = 53.49

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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.