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Finding the Fourth Proportional to 818.20, 1,227.78 and 331.18

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Solution

The fourth proportional to 818.20, 1,227.78 and 331.18 is: 496.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.20 : 1,227.78 = 331.18 : x
  2. Step 2: Convert to fraction form
    818.20/1,227.78 = 331.18/x
  3. Step 3: Cross multiply
    818.20x = 1,227.78 × 331.18
  4. Step 4: Simplify right side
    818.20x = 406,616.18
  5. Step 5: Solve for x
    x = 406,616.18/818.20
  6. Step 6: Final answer
    x = 496.96

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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.