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Finding the Fourth Proportional to 721.27, 994.80 and 621.87

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Solution

The fourth proportional to 721.27, 994.80 and 621.87 is: 857.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.27 : 994.80 = 621.87 : x
  2. Step 2: Convert to fraction form
    721.27/994.80 = 621.87/x
  3. Step 3: Cross multiply
    721.27x = 994.80 × 621.87
  4. Step 4: Simplify right side
    721.27x = 618,636.28
  5. Step 5: Solve for x
    x = 618,636.28/721.27
  6. Step 6: Final answer
    x = 857.70

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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.