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Finding the Fourth Proportional to 47.31, 65.16 and 39.12

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Solution

The fourth proportional to 47.31, 65.16 and 39.12 is: 53.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    47.31 : 65.16 = 39.12 : x
  2. Step 2: Convert to fraction form
    47.31/65.16 = 39.12/x
  3. Step 3: Cross multiply
    47.31x = 65.16 × 39.12
  4. Step 4: Simplify right side
    47.31x = 2,549.06
  5. Step 5: Solve for x
    x = 2,549.06/47.31
  6. Step 6: Final answer
    x = 53.88

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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.