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Finding the Fourth Proportional to 408.66, 612.72 and 278.70

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Solution

The fourth proportional to 408.66, 612.72 and 278.70 is: 417.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.66 : 612.72 = 278.70 : x
  2. Step 2: Convert to fraction form
    408.66/612.72 = 278.70/x
  3. Step 3: Cross multiply
    408.66x = 612.72 × 278.70
  4. Step 4: Simplify right side
    408.66x = 170,765.06
  5. Step 5: Solve for x
    x = 170,765.06/408.66
  6. Step 6: Final answer
    x = 417.87

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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.