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Finding the Fourth Proportional to 77.18, 106.38 and 61.58

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Solution

The fourth proportional to 77.18, 106.38 and 61.58 is: 84.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.18 : 106.38 = 61.58 : x
  2. Step 2: Convert to fraction form
    77.18/106.38 = 61.58/x
  3. Step 3: Cross multiply
    77.18x = 106.38 × 61.58
  4. Step 4: Simplify right side
    77.18x = 6,550.57
  5. Step 5: Solve for x
    x = 6,550.57/77.18
  6. Step 6: Final answer
    x = 84.88

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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.