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Finding the Fourth Proportional to 147.05, 219.07 and 138.20

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Solution

The fourth proportional to 147.05, 219.07 and 138.20 is: 205.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    147.05 : 219.07 = 138.20 : x
  2. Step 2: Convert to fraction form
    147.05/219.07 = 138.20/x
  3. Step 3: Cross multiply
    147.05x = 219.07 × 138.20
  4. Step 4: Simplify right side
    147.05x = 30,274.79
  5. Step 5: Solve for x
    x = 30,274.79/147.05
  6. Step 6: Final answer
    x = 205.88

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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.