Home / 2,212.80-3,315.20-1,287.60

Finding the Fourth Proportional to 2,212.80, 3,315.20 and 1,287.60

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Solution

The fourth proportional to 2,212.80, 3,315.20 and 1,287.60 is: 1,929.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,212.80 : 3,315.20 = 1,287.60 : x
  2. Step 2: Convert to fraction form
    2,212.80/3,315.20 = 1,287.60/x
  3. Step 3: Cross multiply
    2,212.80x = 3,315.20 × 1,287.60
  4. Step 4: Simplify right side
    2,212.80x = 4,268,651.52
  5. Step 5: Solve for x
    x = 4,268,651.52/2,212.80
  6. Step 6: Final answer
    x = 1,929.07

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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.