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Finding the Fourth Proportional to 621.70, 930.72 and 490.78

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Solution

The fourth proportional to 621.70, 930.72 and 490.78 is: 734.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.70 : 930.72 = 490.78 : x
  2. Step 2: Convert to fraction form
    621.70/930.72 = 490.78/x
  3. Step 3: Cross multiply
    621.70x = 930.72 × 490.78
  4. Step 4: Simplify right side
    621.70x = 456,778.76
  5. Step 5: Solve for x
    x = 456,778.76/621.70
  6. Step 6: Final answer
    x = 734.73

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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.