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Finding the Fourth Proportional to 621.15, 930.41 and 490.55

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Solution

The fourth proportional to 621.15, 930.41 and 490.55 is: 734.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.15 : 930.41 = 490.55 : x
  2. Step 2: Convert to fraction form
    621.15/930.41 = 490.55/x
  3. Step 3: Cross multiply
    621.15x = 930.41 × 490.55
  4. Step 4: Simplify right side
    621.15x = 456,405.52
  5. Step 5: Solve for x
    x = 456,405.52/621.15
  6. Step 6: Final answer
    x = 734.78

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.