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Finding the Fourth Proportional to 142.39, 195.21 and 139.79

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Solution

The fourth proportional to 142.39, 195.21 and 139.79 is: 191.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    142.39 : 195.21 = 139.79 : x
  2. Step 2: Convert to fraction form
    142.39/195.21 = 139.79/x
  3. Step 3: Cross multiply
    142.39x = 195.21 × 139.79
  4. Step 4: Simplify right side
    142.39x = 27,289.34
  5. Step 5: Solve for x
    x = 27,289.34/142.39
  6. Step 6: Final answer
    x = 191.66

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.