Home / 1,638.20-2,456.87-815.87

Finding the Fourth Proportional to 1,638.20, 2,456.87 and 815.87

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Solution

The fourth proportional to 1,638.20, 2,456.87 and 815.87 is: 1,223.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,638.20 : 2,456.87 = 815.87 : x
  2. Step 2: Convert to fraction form
    1,638.20/2,456.87 = 815.87/x
  3. Step 3: Cross multiply
    1,638.20x = 2,456.87 × 815.87
  4. Step 4: Simplify right side
    1,638.20x = 2,004,470.16
  5. Step 5: Solve for x
    x = 2,004,470.16/1,638.20
  6. Step 6: Final answer
    x = 1,223.58

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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.