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Finding the Fourth Proportional to 785.67, 1,083.78 and 490.43

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Solution

The fourth proportional to 785.67, 1,083.78 and 490.43 is: 676.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    785.67 : 1,083.78 = 490.43 : x
  2. Step 2: Convert to fraction form
    785.67/1,083.78 = 490.43/x
  3. Step 3: Cross multiply
    785.67x = 1,083.78 × 490.43
  4. Step 4: Simplify right side
    785.67x = 531,517.89
  5. Step 5: Solve for x
    x = 531,517.89/785.67
  6. Step 6: Final answer
    x = 676.51

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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.