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Finding the Fourth Proportional to 155.13, 213.28 and 138.38

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Solution

The fourth proportional to 155.13, 213.28 and 138.38 is: 190.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.13 : 213.28 = 138.38 : x
  2. Step 2: Convert to fraction form
    155.13/213.28 = 138.38/x
  3. Step 3: Cross multiply
    155.13x = 213.28 × 138.38
  4. Step 4: Simplify right side
    155.13x = 29,512.79
  5. Step 5: Solve for x
    x = 29,512.79/155.13
  6. Step 6: Final answer
    x = 190.25

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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.