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Finding the Fourth Proportional to 155.20, 231.77 and 138.19

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Solution

The fourth proportional to 155.20, 231.77 and 138.19 is: 206.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.20 : 231.77 = 138.19 : x
  2. Step 2: Convert to fraction form
    155.20/231.77 = 138.19/x
  3. Step 3: Cross multiply
    155.20x = 231.77 × 138.19
  4. Step 4: Simplify right side
    155.20x = 32,028.06
  5. Step 5: Solve for x
    x = 32,028.06/155.20
  6. Step 6: Final answer
    x = 206.37

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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.