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Finding the Fourth Proportional to 138.46, 207.60 and 89.74

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Solution

The fourth proportional to 138.46, 207.60 and 89.74 is: 134.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.46 : 207.60 = 89.74 : x
  2. Step 2: Convert to fraction form
    138.46/207.60 = 89.74/x
  3. Step 3: Cross multiply
    138.46x = 207.60 × 89.74
  4. Step 4: Simplify right side
    138.46x = 18,630.02
  5. Step 5: Solve for x
    x = 18,630.02/138.46
  6. Step 6: Final answer
    x = 134.55

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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.