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Finding the Fourth Proportional to 645.94, 969 and 213.22

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Solution

The fourth proportional to 645.94, 969 and 213.22 is: 319.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.94 : 969 = 213.22 : x
  2. Step 2: Convert to fraction form
    645.94/969 = 213.22/x
  3. Step 3: Cross multiply
    645.94x = 969 × 213.22
  4. Step 4: Simplify right side
    645.94x = 206,610.18
  5. Step 5: Solve for x
    x = 206,610.18/645.94
  6. Step 6: Final answer
    x = 319.86

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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.