Home / 1,939.29-2,909.39-640.75

Finding the Fourth Proportional to 1,939.29, 2,909.39 and 640.75

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Solution

The fourth proportional to 1,939.29, 2,909.39 and 640.75 is: 961.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,939.29 : 2,909.39 = 640.75 : x
  2. Step 2: Convert to fraction form
    1,939.29/2,909.39 = 640.75/x
  3. Step 3: Cross multiply
    1,939.29x = 2,909.39 × 640.75
  4. Step 4: Simplify right side
    1,939.29x = 1,864,191.64
  5. Step 5: Solve for x
    x = 1,864,191.64/1,939.29
  6. Step 6: Final answer
    x = 961.28

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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.