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Finding the Fourth Proportional to 12, 18 and 6

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Solution

The fourth proportional to 12, 18 and 6 is: 9

Step by Step Solution

  1. Step 1: Write the proportion equation
    12 : 18 = 6 : x
  2. Step 2: Convert to fraction form
    12/18 = 6/x
  3. Step 3: Cross multiply
    12x = 18 × 6
  4. Step 4: Simplify right side
    12x = 108
  5. Step 5: Solve for x
    x = 108/12
  6. Step 6: Final answer
    x = 9

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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.