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Finding the Fourth Proportional to 1,220.39, 1,830.70 and 489.80

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Solution

The fourth proportional to 1,220.39, 1,830.70 and 489.80 is: 734.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,220.39 : 1,830.70 = 489.80 : x
  2. Step 2: Convert to fraction form
    1,220.39/1,830.70 = 489.80/x
  3. Step 3: Cross multiply
    1,220.39x = 1,830.70 × 489.80
  4. Step 4: Simplify right side
    1,220.39x = 896,671.75
  5. Step 5: Solve for x
    x = 896,671.75/1,220.39
  6. Step 6: Final answer
    x = 734.74

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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.