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Finding the Fourth Proportional to 155.20, 231.55 and 139.82

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Solution

The fourth proportional to 155.20, 231.55 and 139.82 is: 208.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.20 : 231.55 = 139.82 : x
  2. Step 2: Convert to fraction form
    155.20/231.55 = 139.82/x
  3. Step 3: Cross multiply
    155.20x = 231.55 × 139.82
  4. Step 4: Simplify right side
    155.20x = 32,375.32
  5. Step 5: Solve for x
    x = 32,375.32/155.20
  6. Step 6: Final answer
    x = 208.60

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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.