Home / 1,939.28-2,909.12-640.24

Finding the Fourth Proportional to 1,939.28, 2,909.12 and 640.24

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Solution

The fourth proportional to 1,939.28, 2,909.12 and 640.24 is: 960.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,939.28 : 2,909.12 = 640.24 : x
  2. Step 2: Convert to fraction form
    1,939.28/2,909.12 = 640.24/x
  3. Step 3: Cross multiply
    1,939.28x = 2,909.12 × 640.24
  4. Step 4: Simplify right side
    1,939.28x = 1,862,534.99
  5. Step 5: Solve for x
    x = 1,862,534.99/1,939.28
  6. Step 6: Final answer
    x = 960.43

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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.