Home / 1,280.80-1,919.20-701.92

Finding the Fourth Proportional to 1,280.80, 1,919.20 and 701.92

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Solution

The fourth proportional to 1,280.80, 1,919.20 and 701.92 is: 1,051.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.80 : 1,919.20 = 701.92 : x
  2. Step 2: Convert to fraction form
    1,280.80/1,919.20 = 701.92/x
  3. Step 3: Cross multiply
    1,280.80x = 1,919.20 × 701.92
  4. Step 4: Simplify right side
    1,280.80x = 1,347,124.86
  5. Step 5: Solve for x
    x = 1,347,124.86/1,280.80
  6. Step 6: Final answer
    x = 1,051.78

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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.