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Finding the Fourth Proportional to 159.78, 220.07 and 137.91

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Solution

The fourth proportional to 159.78, 220.07 and 137.91 is: 189.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    159.78 : 220.07 = 137.91 : x
  2. Step 2: Convert to fraction form
    159.78/220.07 = 137.91/x
  3. Step 3: Cross multiply
    159.78x = 220.07 × 137.91
  4. Step 4: Simplify right side
    159.78x = 30,350.20
  5. Step 5: Solve for x
    x = 30,350.20/159.78
  6. Step 6: Final answer
    x = 189.95

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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.