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Finding the Fourth Proportional to 159.40, 220.23 and 138.61

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Solution

The fourth proportional to 159.40, 220.23 and 138.61 is: 191.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    159.40 : 220.23 = 138.61 : x
  2. Step 2: Convert to fraction form
    159.40/220.23 = 138.61/x
  3. Step 3: Cross multiply
    159.40x = 220.23 × 138.61
  4. Step 4: Simplify right side
    159.40x = 30,526.08
  5. Step 5: Solve for x
    x = 30,526.08/159.40
  6. Step 6: Final answer
    x = 191.51

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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.