Home / 1,213.21-1,819.82-780.09

Finding the Fourth Proportional to 1,213.21, 1,819.82 and 780.09

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Solution

The fourth proportional to 1,213.21, 1,819.82 and 780.09 is: 1,170.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,213.21 : 1,819.82 = 780.09 : x
  2. Step 2: Convert to fraction form
    1,213.21/1,819.82 = 780.09/x
  3. Step 3: Cross multiply
    1,213.21x = 1,819.82 × 780.09
  4. Step 4: Simplify right side
    1,213.21x = 1,419,623.38
  5. Step 5: Solve for x
    x = 1,419,623.38/1,213.21
  6. Step 6: Final answer
    x = 1,170.14

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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.