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Finding the Fourth Proportional to 71.76, 108.02 and 51.61

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Solution

The fourth proportional to 71.76, 108.02 and 51.61 is: 77.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.76 : 108.02 = 51.61 : x
  2. Step 2: Convert to fraction form
    71.76/108.02 = 51.61/x
  3. Step 3: Cross multiply
    71.76x = 108.02 × 51.61
  4. Step 4: Simplify right side
    71.76x = 5,574.91
  5. Step 5: Solve for x
    x = 5,574.91/71.76
  6. Step 6: Final answer
    x = 77.69

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.