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Finding the Fourth Proportional to 155.67, 213.78 and 139.25

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Solution

The fourth proportional to 155.67, 213.78 and 139.25 is: 191.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.67 : 213.78 = 139.25 : x
  2. Step 2: Convert to fraction form
    155.67/213.78 = 139.25/x
  3. Step 3: Cross multiply
    155.67x = 213.78 × 139.25
  4. Step 4: Simplify right side
    155.67x = 29,767.80
  5. Step 5: Solve for x
    x = 29,767.80/155.67
  6. Step 6: Final answer
    x = 191.22

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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.