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Finding the Fourth Proportional to 513.78, 770.85 and 321.18

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Solution

The fourth proportional to 513.78, 770.85 and 321.18 is: 481.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.78 : 770.85 = 321.18 : x
  2. Step 2: Convert to fraction form
    513.78/770.85 = 321.18/x
  3. Step 3: Cross multiply
    513.78x = 770.85 × 321.18
  4. Step 4: Simplify right side
    513.78x = 247,581.60
  5. Step 5: Solve for x
    x = 247,581.60/513.78
  6. Step 6: Final answer
    x = 481.88

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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.