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Finding the Fourth Proportional to 268.65, 403.11 and 138.78

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Solution

The fourth proportional to 268.65, 403.11 and 138.78 is: 208.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    268.65 : 403.11 = 138.78 : x
  2. Step 2: Convert to fraction form
    268.65/403.11 = 138.78/x
  3. Step 3: Cross multiply
    268.65x = 403.11 × 138.78
  4. Step 4: Simplify right side
    268.65x = 55,943.61
  5. Step 5: Solve for x
    x = 55,943.61/268.65
  6. Step 6: Final answer
    x = 208.24

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.