Home / 1,213.21-1,819.98-391.39

Finding the Fourth Proportional to 1,213.21, 1,819.98 and 391.39

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Solution

The fourth proportional to 1,213.21, 1,819.98 and 391.39 is: 587.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,213.21 : 1,819.98 = 391.39 : x
  2. Step 2: Convert to fraction form
    1,213.21/1,819.98 = 391.39/x
  3. Step 3: Cross multiply
    1,213.21x = 1,819.98 × 391.39
  4. Step 4: Simplify right side
    1,213.21x = 712,321.97
  5. Step 5: Solve for x
    x = 712,321.97/1,213.21
  6. Step 6: Final answer
    x = 587.14

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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.