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Finding the Fourth Proportional to 155.50, 214.17 and 139.90

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Solution

The fourth proportional to 155.50, 214.17 and 139.90 is: 192.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.50 : 214.17 = 139.90 : x
  2. Step 2: Convert to fraction form
    155.50/214.17 = 139.90/x
  3. Step 3: Cross multiply
    155.50x = 214.17 × 139.90
  4. Step 4: Simplify right side
    155.50x = 29,962.38
  5. Step 5: Solve for x
    x = 29,962.38/155.50
  6. Step 6: Final answer
    x = 192.68

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.