Home / 2,120.30-3,180.42-820.85

Finding the Fourth Proportional to 2,120.30, 3,180.42 and 820.85

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Solution

The fourth proportional to 2,120.30, 3,180.42 and 820.85 is: 1,231.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,120.30 : 3,180.42 = 820.85 : x
  2. Step 2: Convert to fraction form
    2,120.30/3,180.42 = 820.85/x
  3. Step 3: Cross multiply
    2,120.30x = 3,180.42 × 820.85
  4. Step 4: Simplify right side
    2,120.30x = 2,610,647.76
  5. Step 5: Solve for x
    x = 2,610,647.76/2,120.30
  6. Step 6: Final answer
    x = 1,231.26

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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.