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Finding the Fourth Proportional to 409.09, 613.40 and 279.24

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Solution

The fourth proportional to 409.09, 613.40 and 279.24 is: 418.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.09 : 613.40 = 279.24 : x
  2. Step 2: Convert to fraction form
    409.09/613.40 = 279.24/x
  3. Step 3: Cross multiply
    409.09x = 613.40 × 279.24
  4. Step 4: Simplify right side
    409.09x = 171,286.83
  5. Step 5: Solve for x
    x = 171,286.83/409.09
  6. Step 6: Final answer
    x = 418.71

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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.