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Finding the Third Proportional to 18 and 27

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Solution

The third proportional to 18 and 27 is: 40.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    18 : 27 = 27 : x
  2. Step 2: Convert to fraction form
    18/27 = 27/x
  3. Step 3: Cross multiply
    18x = 27 × 27
  4. Step 4: Simplify right side
    18x = 729
  5. Step 5: Solve for x
    x = 729/18
  6. Step 6: Final answer
    x = 40.50

Related Problems

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Double scale
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Similar ratio
Find third proportional to 27 and 40.50
1.5x scale

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.