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Finding the Fourth Proportional to 1,939.70, 2,909.97 and 641.09

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Solution

The fourth proportional to 1,939.70, 2,909.97 and 641.09 is: 961.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,939.70 : 2,909.97 = 641.09 : x
  2. Step 2: Convert to fraction form
    1,939.70/2,909.97 = 641.09/x
  3. Step 3: Cross multiply
    1,939.70x = 2,909.97 × 641.09
  4. Step 4: Simplify right side
    1,939.70x = 1,865,538.12
  5. Step 5: Solve for x
    x = 1,865,538.12/1,939.70
  6. Step 6: Final answer
    x = 961.77

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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.