Home / 1,939.80-2,909.99-640.96

Finding the Fourth Proportional to 1,939.80, 2,909.99 and 640.96

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Solution

The fourth proportional to 1,939.80, 2,909.99 and 640.96 is: 961.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,939.80 : 2,909.99 = 640.96 : x
  2. Step 2: Convert to fraction form
    1,939.80/2,909.99 = 640.96/x
  3. Step 3: Cross multiply
    1,939.80x = 2,909.99 × 640.96
  4. Step 4: Simplify right side
    1,939.80x = 1,865,187.19
  5. Step 5: Solve for x
    x = 1,865,187.19/1,939.80
  6. Step 6: Final answer
    x = 961.54

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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.