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Finding the Fourth Proportional to 645.97, 969.11 and 213.13

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Solution

The fourth proportional to 645.97, 969.11 and 213.13 is: 319.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.97 : 969.11 = 213.13 : x
  2. Step 2: Convert to fraction form
    645.97/969.11 = 213.13/x
  3. Step 3: Cross multiply
    645.97x = 969.11 × 213.13
  4. Step 4: Simplify right side
    645.97x = 206,540.50
  5. Step 5: Solve for x
    x = 206,540.50/645.97
  6. Step 6: Final answer
    x = 319.74

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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.