Home / 1,378.89-2,069.69-1,121.85

Finding the Fourth Proportional to 1,378.89, 2,069.69 and 1,121.85

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Solution

The fourth proportional to 1,378.89, 2,069.69 and 1,121.85 is: 1,683.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,378.89 : 2,069.69 = 1,121.85 : x
  2. Step 2: Convert to fraction form
    1,378.89/2,069.69 = 1,121.85/x
  3. Step 3: Cross multiply
    1,378.89x = 2,069.69 × 1,121.85
  4. Step 4: Simplify right side
    1,378.89x = 2,321,876.12
  5. Step 5: Solve for x
    x = 2,321,876.12/1,378.89
  6. Step 6: Final answer
    x = 1,683.87

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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.