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Finding the Fourth Proportional to 1,659.78, 2,489.67 and 489.80

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Solution

The fourth proportional to 1,659.78, 2,489.67 and 489.80 is: 734.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,659.78 : 2,489.67 = 489.80 : x
  2. Step 2: Convert to fraction form
    1,659.78/2,489.67 = 489.80/x
  3. Step 3: Cross multiply
    1,659.78x = 2,489.67 × 489.80
  4. Step 4: Simplify right side
    1,659.78x = 1,219,445.16
  5. Step 5: Solve for x
    x = 1,219,445.16/1,659.78
  6. Step 6: Final answer
    x = 734.70

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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.