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Finding the Third Proportional to 15 and 30

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Solution

The third proportional to 15 and 30 is: 60

Step by Step Solution

  1. Step 1: Write the proportion equation
    15 : 30 = 30 : x
  2. Step 2: Convert to fraction form
    15/30 = 30/x
  3. Step 3: Cross multiply
    15x = 30 × 30
  4. Step 4: Simplify right side
    15x = 900
  5. Step 5: Solve for x
    x = 900/15
  6. Step 6: Final answer
    x = 60

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Why These Related Problems?

These problems maintain the same ratio (2) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.