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Finding the Fourth Proportional to 66.87, 100.08 and 61.18

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Solution

The fourth proportional to 66.87, 100.08 and 61.18 is: 91.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.87 : 100.08 = 61.18 : x
  2. Step 2: Convert to fraction form
    66.87/100.08 = 61.18/x
  3. Step 3: Cross multiply
    66.87x = 100.08 × 61.18
  4. Step 4: Simplify right side
    66.87x = 6,122.09
  5. Step 5: Solve for x
    x = 6,122.09/66.87
  6. Step 6: Final answer
    x = 91.55

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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.