Home / 2,120.68-3,180.52-639.60

Finding the Fourth Proportional to 2,120.68, 3,180.52 and 639.60

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Solution

The fourth proportional to 2,120.68, 3,180.52 and 639.60 is: 959.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,120.68 : 3,180.52 = 639.60 : x
  2. Step 2: Convert to fraction form
    2,120.68/3,180.52 = 639.60/x
  3. Step 3: Cross multiply
    2,120.68x = 3,180.52 × 639.60
  4. Step 4: Simplify right side
    2,120.68x = 2,034,245.87
  5. Step 5: Solve for x
    x = 2,034,245.87/2,120.68
  6. Step 6: Final answer
    x = 959.24

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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.