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Finding the Fourth Proportional to 47.70, 71.52 and 39.66

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Solution

The fourth proportional to 47.70, 71.52 and 39.66 is: 59.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    47.70 : 71.52 = 39.66 : x
  2. Step 2: Convert to fraction form
    47.70/71.52 = 39.66/x
  3. Step 3: Cross multiply
    47.70x = 71.52 × 39.66
  4. Step 4: Simplify right side
    47.70x = 2,836.48
  5. Step 5: Solve for x
    x = 2,836.48/47.70
  6. Step 6: Final answer
    x = 59.47

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.