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Finding the Fourth Proportional to 499.20, 748.80 and 306.78

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Solution

The fourth proportional to 499.20, 748.80 and 306.78 is: 460.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.20 : 748.80 = 306.78 : x
  2. Step 2: Convert to fraction form
    499.20/748.80 = 306.78/x
  3. Step 3: Cross multiply
    499.20x = 748.80 × 306.78
  4. Step 4: Simplify right side
    499.20x = 229,716.86
  5. Step 5: Solve for x
    x = 229,716.86/499.20
  6. Step 6: Final answer
    x = 460.17

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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.