Home / 2,120.81-3,180.20-659.97

Finding the Fourth Proportional to 2,120.81, 3,180.20 and 659.97

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Solution

The fourth proportional to 2,120.81, 3,180.20 and 659.97 is: 989.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,120.81 : 3,180.20 = 659.97 : x
  2. Step 2: Convert to fraction form
    2,120.81/3,180.20 = 659.97/x
  3. Step 3: Cross multiply
    2,120.81x = 3,180.20 × 659.97
  4. Step 4: Simplify right side
    2,120.81x = 2,098,833.29
  5. Step 5: Solve for x
    x = 2,098,833.29/2,120.81
  6. Step 6: Final answer
    x = 989.64

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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.