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Finding the Fourth Proportional to 138.80, 191.64 and 119.60

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Solution

The fourth proportional to 138.80, 191.64 and 119.60 is: 165.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.80 : 191.64 = 119.60 : x
  2. Step 2: Convert to fraction form
    138.80/191.64 = 119.60/x
  3. Step 3: Cross multiply
    138.80x = 191.64 × 119.60
  4. Step 4: Simplify right side
    138.80x = 22,920.14
  5. Step 5: Solve for x
    x = 22,920.14/138.80
  6. Step 6: Final answer
    x = 165.13

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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.