Home / 1,939.20-2,909.10-640.26

Finding the Fourth Proportional to 1,939.20, 2,909.10 and 640.26

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Solution

The fourth proportional to 1,939.20, 2,909.10 and 640.26 is: 960.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,939.20 : 2,909.10 = 640.26 : x
  2. Step 2: Convert to fraction form
    1,939.20/2,909.10 = 640.26/x
  3. Step 3: Cross multiply
    1,939.20x = 2,909.10 × 640.26
  4. Step 4: Simplify right side
    1,939.20x = 1,862,580.37
  5. Step 5: Solve for x
    x = 1,862,580.37/1,939.20
  6. Step 6: Final answer
    x = 960.49

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1.5x scale

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.