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Finding the Fourth Proportional to 138.30, 206.57 and 119.10

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Solution

The fourth proportional to 138.30, 206.57 and 119.10 is: 177.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.30 : 206.57 = 119.10 : x
  2. Step 2: Convert to fraction form
    138.30/206.57 = 119.10/x
  3. Step 3: Cross multiply
    138.30x = 206.57 × 119.10
  4. Step 4: Simplify right side
    138.30x = 24,601.89
  5. Step 5: Solve for x
    x = 24,601.89/138.30
  6. Step 6: Final answer
    x = 177.89

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.