Home / 2,815.80-4,223.70-1,279.80

Finding the Fourth Proportional to 2,815.80, 4,223.70 and 1,279.80

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Solution

The fourth proportional to 2,815.80, 4,223.70 and 1,279.80 is: 1,919.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,815.80 : 4,223.70 = 1,279.80 : x
  2. Step 2: Convert to fraction form
    2,815.80/4,223.70 = 1,279.80/x
  3. Step 3: Cross multiply
    2,815.80x = 4,223.70 × 1,279.80
  4. Step 4: Simplify right side
    2,815.80x = 5,405,491.26
  5. Step 5: Solve for x
    x = 5,405,491.26/2,815.80
  6. Step 6: Final answer
    x = 1,919.70

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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.