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Finding the Fourth Proportional to 821.05, 1,231.17 and 604.78

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Solution

The fourth proportional to 821.05, 1,231.17 and 604.78 is: 906.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    821.05 : 1,231.17 = 604.78 : x
  2. Step 2: Convert to fraction form
    821.05/1,231.17 = 604.78/x
  3. Step 3: Cross multiply
    821.05x = 1,231.17 × 604.78
  4. Step 4: Simplify right side
    821.05x = 744,586.99
  5. Step 5: Solve for x
    x = 744,586.99/821.05
  6. Step 6: Final answer
    x = 906.87

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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.