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Finding the Fourth Proportional to 724.55, 999.90 and 409.80

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Solution

The fourth proportional to 724.55, 999.90 and 409.80 is: 565.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    724.55 : 999.90 = 409.80 : x
  2. Step 2: Convert to fraction form
    724.55/999.90 = 409.80/x
  3. Step 3: Cross multiply
    724.55x = 999.90 × 409.80
  4. Step 4: Simplify right side
    724.55x = 409,759.02
  5. Step 5: Solve for x
    x = 409,759.02/724.55
  6. Step 6: Final answer
    x = 565.54

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.