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Finding the Fourth Proportional to 778.91, 1,074.57 and 447.15

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Solution

The fourth proportional to 778.91, 1,074.57 and 447.15 is: 616.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    778.91 : 1,074.57 = 447.15 : x
  2. Step 2: Convert to fraction form
    778.91/1,074.57 = 447.15/x
  3. Step 3: Cross multiply
    778.91x = 1,074.57 × 447.15
  4. Step 4: Simplify right side
    778.91x = 480,493.98
  5. Step 5: Solve for x
    x = 480,493.98/778.91
  6. Step 6: Final answer
    x = 616.88

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.