Home / 21,286.11-31,929.21-8,139.81

Finding the Fourth Proportional to 21,286.11, 31,929.21 and 8,139.81

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Solution

The fourth proportional to 21,286.11, 31,929.21 and 8,139.81 is: 12,209.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,286.11 : 31,929.21 = 8,139.81 : x
  2. Step 2: Convert to fraction form
    21,286.11/31,929.21 = 8,139.81/x
  3. Step 3: Cross multiply
    21,286.11x = 31,929.21 × 8,139.81
  4. Step 4: Simplify right side
    21,286.11x = 259,897,702.85
  5. Step 5: Solve for x
    x = 259,897,702.85/21,286.11
  6. Step 6: Final answer
    x = 12,209.73

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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.