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Finding the Fourth Proportional to 249.20, 343.88 and 138.67

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Solution

The fourth proportional to 249.20, 343.88 and 138.67 is: 191.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    249.20 : 343.88 = 138.67 : x
  2. Step 2: Convert to fraction form
    249.20/343.88 = 138.67/x
  3. Step 3: Cross multiply
    249.20x = 343.88 × 138.67
  4. Step 4: Simplify right side
    249.20x = 47,687.81
  5. Step 5: Solve for x
    x = 47,687.81/249.20
  6. Step 6: Final answer
    x = 191.36

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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.