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Finding the Fourth Proportional to 721.20, 995.10 and 410.70

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Solution

The fourth proportional to 721.20, 995.10 and 410.70 is: 566.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.20 : 995.10 = 410.70 : x
  2. Step 2: Convert to fraction form
    721.20/995.10 = 410.70/x
  3. Step 3: Cross multiply
    721.20x = 995.10 × 410.70
  4. Step 4: Simplify right side
    721.20x = 408,687.57
  5. Step 5: Solve for x
    x = 408,687.57/721.20
  6. Step 6: Final answer
    x = 566.68

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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.