Home / 1,638.60-2,458.26-815.82

Finding the Fourth Proportional to 1,638.60, 2,458.26 and 815.82

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Solution

The fourth proportional to 1,638.60, 2,458.26 and 815.82 is: 1,223.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,638.60 : 2,458.26 = 815.82 : x
  2. Step 2: Convert to fraction form
    1,638.60/2,458.26 = 815.82/x
  3. Step 3: Cross multiply
    1,638.60x = 2,458.26 × 815.82
  4. Step 4: Simplify right side
    1,638.60x = 2,005,497.67
  5. Step 5: Solve for x
    x = 2,005,497.67/1,638.60
  6. Step 6: Final answer
    x = 1,223.91

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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.