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Finding the Fourth Proportional to 400.20, 552.15 and 306.78

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Solution

The fourth proportional to 400.20, 552.15 and 306.78 is: 423.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    400.20 : 552.15 = 306.78 : x
  2. Step 2: Convert to fraction form
    400.20/552.15 = 306.78/x
  3. Step 3: Cross multiply
    400.20x = 552.15 × 306.78
  4. Step 4: Simplify right side
    400.20x = 169,388.58
  5. Step 5: Solve for x
    x = 169,388.58/400.20
  6. Step 6: Final answer
    x = 423.26

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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.