Home / 1,280.20-1,920.60-402.76

Finding the Fourth Proportional to 1,280.20, 1,920.60 and 402.76

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Solution

The fourth proportional to 1,280.20, 1,920.60 and 402.76 is: 604.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.20 : 1,920.60 = 402.76 : x
  2. Step 2: Convert to fraction form
    1,280.20/1,920.60 = 402.76/x
  3. Step 3: Cross multiply
    1,280.20x = 1,920.60 × 402.76
  4. Step 4: Simplify right side
    1,280.20x = 773,540.86
  5. Step 5: Solve for x
    x = 773,540.86/1,280.20
  6. Step 6: Final answer
    x = 604.23

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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.