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Finding the Fourth Proportional to 784.85, 1,083.31 and 489.95

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Solution

The fourth proportional to 784.85, 1,083.31 and 489.95 is: 676.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    784.85 : 1,083.31 = 489.95 : x
  2. Step 2: Convert to fraction form
    784.85/1,083.31 = 489.95/x
  3. Step 3: Cross multiply
    784.85x = 1,083.31 × 489.95
  4. Step 4: Simplify right side
    784.85x = 530,761.09
  5. Step 5: Solve for x
    x = 530,761.09/784.85
  6. Step 6: Final answer
    x = 676.26

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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.