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Finding the Fourth Proportional to 409.31, 613.90 and 214.19

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Solution

The fourth proportional to 409.31, 613.90 and 214.19 is: 321.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    409.31 : 613.90 = 214.19 : x
  2. Step 2: Convert to fraction form
    409.31/613.90 = 214.19/x
  3. Step 3: Cross multiply
    409.31x = 613.90 × 214.19
  4. Step 4: Simplify right side
    409.31x = 131,491.24
  5. Step 5: Solve for x
    x = 131,491.24/409.31
  6. Step 6: Final answer
    x = 321.25

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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.