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Finding the Third Proportional to 18 and 30

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Solution

The third proportional to 18 and 30 is: 50

Step by Step Solution

  1. Step 1: Write the proportion equation
    18 : 30 = 30 : x
  2. Step 2: Convert to fraction form
    18/30 = 30/x
  3. Step 3: Cross multiply
    18x = 30 × 30
  4. Step 4: Simplify right side
    18x = 900
  5. Step 5: Solve for x
    x = 900/18
  6. Step 6: Final answer
    x = 50

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Why These Related Problems?

These problems maintain the same ratio (1.67) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.