Home / 1,939.60-2,909.44-640.96

Finding the Fourth Proportional to 1,939.60, 2,909.44 and 640.96

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Solution

The fourth proportional to 1,939.60, 2,909.44 and 640.96 is: 961.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,939.60 : 2,909.44 = 640.96 : x
  2. Step 2: Convert to fraction form
    1,939.60/2,909.44 = 640.96/x
  3. Step 3: Cross multiply
    1,939.60x = 2,909.44 × 640.96
  4. Step 4: Simplify right side
    1,939.60x = 1,864,834.66
  5. Step 5: Solve for x
    x = 1,864,834.66/1,939.60
  6. Step 6: Final answer
    x = 961.45

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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.