Home / 2,120.58-3,179.70-639.60

Finding the Fourth Proportional to 2,120.58, 3,179.70 and 639.60

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Solution

The fourth proportional to 2,120.58, 3,179.70 and 639.60 is: 959.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,120.58 : 3,179.70 = 639.60 : x
  2. Step 2: Convert to fraction form
    2,120.58/3,179.70 = 639.60/x
  3. Step 3: Cross multiply
    2,120.58x = 3,179.70 × 639.60
  4. Step 4: Simplify right side
    2,120.58x = 2,033,736.12
  5. Step 5: Solve for x
    x = 2,033,736.12/2,120.58
  6. Step 6: Final answer
    x = 959.05

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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.