Home / 1,939.23-2,909.30-640.80

Finding the Fourth Proportional to 1,939.23, 2,909.30 and 640.80

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Solution

The fourth proportional to 1,939.23, 2,909.30 and 640.80 is: 961.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,939.23 : 2,909.30 = 640.80 : x
  2. Step 2: Convert to fraction form
    1,939.23/2,909.30 = 640.80/x
  3. Step 3: Cross multiply
    1,939.23x = 2,909.30 × 640.80
  4. Step 4: Simplify right side
    1,939.23x = 1,864,276.24
  5. Step 5: Solve for x
    x = 1,864,276.24/1,939.23
  6. Step 6: Final answer
    x = 961.35

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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.