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Finding the Fourth Proportional to 408.90, 611.10 and 321.18

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Solution

The fourth proportional to 408.90, 611.10 and 321.18 is: 480.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.90 : 611.10 = 321.18 : x
  2. Step 2: Convert to fraction form
    408.90/611.10 = 321.18/x
  3. Step 3: Cross multiply
    408.90x = 611.10 × 321.18
  4. Step 4: Simplify right side
    408.90x = 196,273.10
  5. Step 5: Solve for x
    x = 196,273.10/408.90
  6. Step 6: Final answer
    x = 480.00

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.