Home / 2,142.70-3,213.91-1,321.09

Finding the Fourth Proportional to 2,142.70, 3,213.91 and 1,321.09

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Solution

The fourth proportional to 2,142.70, 3,213.91 and 1,321.09 is: 1,981.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,142.70 : 3,213.91 = 1,321.09 : x
  2. Step 2: Convert to fraction form
    2,142.70/3,213.91 = 1,321.09/x
  3. Step 3: Cross multiply
    2,142.70x = 3,213.91 × 1,321.09
  4. Step 4: Simplify right side
    2,142.70x = 4,245,864.36
  5. Step 5: Solve for x
    x = 4,245,864.36/2,142.70
  6. Step 6: Final answer
    x = 1,981.55

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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.