Home / 21,279.21-31,920.92-8,142.63

Finding the Fourth Proportional to 21,279.21, 31,920.92 and 8,142.63

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Solution

The fourth proportional to 21,279.21, 31,920.92 and 8,142.63 is: 12,214.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,279.21 : 31,920.92 = 8,142.63 : x
  2. Step 2: Convert to fraction form
    21,279.21/31,920.92 = 8,142.63/x
  3. Step 3: Cross multiply
    21,279.21x = 31,920.92 × 8,142.63
  4. Step 4: Simplify right side
    21,279.21x = 259,920,240.82
  5. Step 5: Solve for x
    x = 259,920,240.82/21,279.21
  6. Step 6: Final answer
    x = 12,214.75

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1.5x scale

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.