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Finding the Fourth Proportional to 629.22, 939.80 and 490.78

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Solution

The fourth proportional to 629.22, 939.80 and 490.78 is: 733.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.22 : 939.80 = 490.78 : x
  2. Step 2: Convert to fraction form
    629.22/939.80 = 490.78/x
  3. Step 3: Cross multiply
    629.22x = 939.80 × 490.78
  4. Step 4: Simplify right side
    629.22x = 461,240.09
  5. Step 5: Solve for x
    x = 461,240.09/629.22
  6. Step 6: Final answer
    x = 733.04

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.