Home / 1,287.44-1,784.76-1,217.28

Finding the Fourth Proportional to 1,287.44, 1,784.76 and 1,217.28

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Solution

The fourth proportional to 1,287.44, 1,784.76 and 1,217.28 is: 1,687.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.44 : 1,784.76 = 1,217.28 : x
  2. Step 2: Convert to fraction form
    1,287.44/1,784.76 = 1,217.28/x
  3. Step 3: Cross multiply
    1,287.44x = 1,784.76 × 1,217.28
  4. Step 4: Simplify right side
    1,287.44x = 2,172,552.65
  5. Step 5: Solve for x
    x = 2,172,552.65/1,287.44
  6. Step 6: Final answer
    x = 1,687.50

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.