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Finding the Fourth Proportional to 836.70, 1,255.30 and 489.40

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Solution

The fourth proportional to 836.70, 1,255.30 and 489.40 is: 734.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    836.70 : 1,255.30 = 489.40 : x
  2. Step 2: Convert to fraction form
    836.70/1,255.30 = 489.40/x
  3. Step 3: Cross multiply
    836.70x = 1,255.30 × 489.40
  4. Step 4: Simplify right side
    836.70x = 614,343.82
  5. Step 5: Solve for x
    x = 614,343.82/836.70
  6. Step 6: Final answer
    x = 734.25

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.