Home / 1,287.20-1,919.49-1,275.50

Finding the Fourth Proportional to 1,287.20, 1,919.49 and 1,275.50

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Solution

The fourth proportional to 1,287.20, 1,919.49 and 1,275.50 is: 1,902.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.20 : 1,919.49 = 1,275.50 : x
  2. Step 2: Convert to fraction form
    1,287.20/1,919.49 = 1,275.50/x
  3. Step 3: Cross multiply
    1,287.20x = 1,919.49 × 1,275.50
  4. Step 4: Simplify right side
    1,287.20x = 2,448,309.50
  5. Step 5: Solve for x
    x = 2,448,309.50/1,287.20
  6. Step 6: Final answer
    x = 1,902.05

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.