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Finding the Fourth Proportional to 721.25, 995.28 and 422.55

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Solution

The fourth proportional to 721.25, 995.28 and 422.55 is: 583.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.25 : 995.28 = 422.55 : x
  2. Step 2: Convert to fraction form
    721.25/995.28 = 422.55/x
  3. Step 3: Cross multiply
    721.25x = 995.28 × 422.55
  4. Step 4: Simplify right side
    721.25x = 420,555.56
  5. Step 5: Solve for x
    x = 420,555.56/721.25
  6. Step 6: Final answer
    x = 583.10

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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.