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Finding the Fourth Proportional to 862.30, 1,189.89 and 489.29

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Solution

The fourth proportional to 862.30, 1,189.89 and 489.29 is: 675.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    862.30 : 1,189.89 = 489.29 : x
  2. Step 2: Convert to fraction form
    862.30/1,189.89 = 489.29/x
  3. Step 3: Cross multiply
    862.30x = 1,189.89 × 489.29
  4. Step 4: Simplify right side
    862.30x = 582,201.28
  5. Step 5: Solve for x
    x = 582,201.28/862.30
  6. Step 6: Final answer
    x = 675.17

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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.