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Finding the Fourth Proportional to 137.58, 206.39 and 82.78

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Solution

The fourth proportional to 137.58, 206.39 and 82.78 is: 124.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.58 : 206.39 = 82.78 : x
  2. Step 2: Convert to fraction form
    137.58/206.39 = 82.78/x
  3. Step 3: Cross multiply
    137.58x = 206.39 × 82.78
  4. Step 4: Simplify right side
    137.58x = 17,084.96
  5. Step 5: Solve for x
    x = 17,084.96/137.58
  6. Step 6: Final answer
    x = 124.18

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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.