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Finding the Fourth Proportional to 459.20, 688.80 and 408.80

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Solution

The fourth proportional to 459.20, 688.80 and 408.80 is: 613.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    459.20 : 688.80 = 408.80 : x
  2. Step 2: Convert to fraction form
    459.20/688.80 = 408.80/x
  3. Step 3: Cross multiply
    459.20x = 688.80 × 408.80
  4. Step 4: Simplify right side
    459.20x = 281,581.44
  5. Step 5: Solve for x
    x = 281,581.44/459.20
  6. Step 6: Final answer
    x = 613.20

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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.