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Finding the Fourth Proportional to 645.98, 969.12 and 213.14

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Solution

The fourth proportional to 645.98, 969.12 and 213.14 is: 319.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.98 : 969.12 = 213.14 : x
  2. Step 2: Convert to fraction form
    645.98/969.12 = 213.14/x
  3. Step 3: Cross multiply
    645.98x = 969.12 × 213.14
  4. Step 4: Simplify right side
    645.98x = 206,558.24
  5. Step 5: Solve for x
    x = 206,558.24/645.98
  6. Step 6: Final answer
    x = 319.76

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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.