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Finding the Fourth Proportional to 513.09, 769.31 and 220.78

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Solution

The fourth proportional to 513.09, 769.31 and 220.78 is: 331.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.09 : 769.31 = 220.78 : x
  2. Step 2: Convert to fraction form
    513.09/769.31 = 220.78/x
  3. Step 3: Cross multiply
    513.09x = 769.31 × 220.78
  4. Step 4: Simplify right side
    513.09x = 169,848.26
  5. Step 5: Solve for x
    x = 169,848.26/513.09
  6. Step 6: Final answer
    x = 331.03

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Double scale
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Similar ratio
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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.