Home / 1,439.20-2,158.40-398.95

Finding the Fourth Proportional to 1,439.20, 2,158.40 and 398.95

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Solution

The fourth proportional to 1,439.20, 2,158.40 and 398.95 is: 598.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,439.20 : 2,158.40 = 398.95 : x
  2. Step 2: Convert to fraction form
    1,439.20/2,158.40 = 398.95/x
  3. Step 3: Cross multiply
    1,439.20x = 2,158.40 × 398.95
  4. Step 4: Simplify right side
    1,439.20x = 861,091.69
  5. Step 5: Solve for x
    x = 861,091.69/1,439.20
  6. Step 6: Final answer
    x = 598.31

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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.