Home / 2,120.85-3,181.38-659.82

Finding the Fourth Proportional to 2,120.85, 3,181.38 and 659.82

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Solution

The fourth proportional to 2,120.85, 3,181.38 and 659.82 is: 989.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,120.85 : 3,181.38 = 659.82 : x
  2. Step 2: Convert to fraction form
    2,120.85/3,181.38 = 659.82/x
  3. Step 3: Cross multiply
    2,120.85x = 3,181.38 × 659.82
  4. Step 4: Simplify right side
    2,120.85x = 2,099,138.15
  5. Step 5: Solve for x
    x = 2,099,138.15/2,120.85
  6. Step 6: Final answer
    x = 989.76

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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.