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Finding the Fourth Proportional to 80.62, 111.08 and 61.18

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Solution

The fourth proportional to 80.62, 111.08 and 61.18 is: 84.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.62 : 111.08 = 61.18 : x
  2. Step 2: Convert to fraction form
    80.62/111.08 = 61.18/x
  3. Step 3: Cross multiply
    80.62x = 111.08 × 61.18
  4. Step 4: Simplify right side
    80.62x = 6,795.87
  5. Step 5: Solve for x
    x = 6,795.87/80.62
  6. Step 6: Final answer
    x = 84.30

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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.