Home / 1,338.20-2,004.60-689.30

Finding the Fourth Proportional to 1,338.20, 2,004.60 and 689.30

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Solution

The fourth proportional to 1,338.20, 2,004.60 and 689.30 is: 1,032.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,338.20 : 2,004.60 = 689.30 : x
  2. Step 2: Convert to fraction form
    1,338.20/2,004.60 = 689.30/x
  3. Step 3: Cross multiply
    1,338.20x = 2,004.60 × 689.30
  4. Step 4: Simplify right side
    1,338.20x = 1,381,770.78
  5. Step 5: Solve for x
    x = 1,381,770.78/1,338.20
  6. Step 6: Final answer
    x = 1,032.56

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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.