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Finding the Fourth Proportional to 721.37, 994.20 and 621.53

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Solution

The fourth proportional to 721.37, 994.20 and 621.53 is: 856.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.37 : 994.20 = 621.53 : x
  2. Step 2: Convert to fraction form
    721.37/994.20 = 621.53/x
  3. Step 3: Cross multiply
    721.37x = 994.20 × 621.53
  4. Step 4: Simplify right side
    721.37x = 617,920.16
  5. Step 5: Solve for x
    x = 617,920.16/721.37
  6. Step 6: Final answer
    x = 856.60

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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.