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Finding the Fourth Proportional to 518.80, 778.20 and 299.76

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Solution

The fourth proportional to 518.80, 778.20 and 299.76 is: 449.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.80 : 778.20 = 299.76 : x
  2. Step 2: Convert to fraction form
    518.80/778.20 = 299.76/x
  3. Step 3: Cross multiply
    518.80x = 778.20 × 299.76
  4. Step 4: Simplify right side
    518.80x = 233,269.19
  5. Step 5: Solve for x
    x = 233,269.19/518.80
  6. Step 6: Final answer
    x = 449.63

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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.