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Finding the Fourth Proportional to 826.80, 1,240.20 and 278.92

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Solution

The fourth proportional to 826.80, 1,240.20 and 278.92 is: 418.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    826.80 : 1,240.20 = 278.92 : x
  2. Step 2: Convert to fraction form
    826.80/1,240.20 = 278.92/x
  3. Step 3: Cross multiply
    826.80x = 1,240.20 × 278.92
  4. Step 4: Simplify right side
    826.80x = 345,916.58
  5. Step 5: Solve for x
    x = 345,916.58/826.80
  6. Step 6: Final answer
    x = 418.38

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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.