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Finding the Fourth Proportional to 724.20, 999.40 and 429.60

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Solution

The fourth proportional to 724.20, 999.40 and 429.60 is: 592.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    724.20 : 999.40 = 429.60 : x
  2. Step 2: Convert to fraction form
    724.20/999.40 = 429.60/x
  3. Step 3: Cross multiply
    724.20x = 999.40 × 429.60
  4. Step 4: Simplify right side
    724.20x = 429,342.24
  5. Step 5: Solve for x
    x = 429,342.24/724.20
  6. Step 6: Final answer
    x = 592.85

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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.