Home / 1,280.20-1,917.60-702.40

Finding the Fourth Proportional to 1,280.20, 1,917.60 and 702.40

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Solution

The fourth proportional to 1,280.20, 1,917.60 and 702.40 is: 1,052.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.20 : 1,917.60 = 702.40 : x
  2. Step 2: Convert to fraction form
    1,280.20/1,917.60 = 702.40/x
  3. Step 3: Cross multiply
    1,280.20x = 1,917.60 × 702.40
  4. Step 4: Simplify right side
    1,280.20x = 1,346,922.24
  5. Step 5: Solve for x
    x = 1,346,922.24/1,280.20
  6. Step 6: Final answer
    x = 1,052.12

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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.