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Finding the Fourth Proportional to 826.25, 1,239.36 and 278.81

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Solution

The fourth proportional to 826.25, 1,239.36 and 278.81 is: 418.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    826.25 : 1,239.36 = 278.81 : x
  2. Step 2: Convert to fraction form
    826.25/1,239.36 = 278.81/x
  3. Step 3: Cross multiply
    826.25x = 1,239.36 × 278.81
  4. Step 4: Simplify right side
    826.25x = 345,545.96
  5. Step 5: Solve for x
    x = 345,545.96/826.25
  6. Step 6: Final answer
    x = 418.21

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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.