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Finding the Fourth Proportional to 71.30, 106.75 and 39.18

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Solution

The fourth proportional to 71.30, 106.75 and 39.18 is: 58.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.30 : 106.75 = 39.18 : x
  2. Step 2: Convert to fraction form
    71.30/106.75 = 39.18/x
  3. Step 3: Cross multiply
    71.30x = 106.75 × 39.18
  4. Step 4: Simplify right side
    71.30x = 4,182.47
  5. Step 5: Solve for x
    x = 4,182.47/71.30
  6. Step 6: Final answer
    x = 58.66

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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.