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Finding the Fourth Proportional to 783.80, 1,081.32 and 489.44

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Solution

The fourth proportional to 783.80, 1,081.32 and 489.44 is: 675.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    783.80 : 1,081.32 = 489.44 : x
  2. Step 2: Convert to fraction form
    783.80/1,081.32 = 489.44/x
  3. Step 3: Cross multiply
    783.80x = 1,081.32 × 489.44
  4. Step 4: Simplify right side
    783.80x = 529,241.26
  5. Step 5: Solve for x
    x = 529,241.26/783.80
  6. Step 6: Final answer
    x = 675.22

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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.