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Finding the Third Proportional to 11 and 13

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Solution

The third proportional to 11 and 13 is: 15.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    11 : 13 = 13 : x
  2. Step 2: Convert to fraction form
    11/13 = 13/x
  3. Step 3: Cross multiply
    11x = 13 × 13
  4. Step 4: Simplify right side
    11x = 169
  5. Step 5: Solve for x
    x = 169/11
  6. Step 6: Final answer
    x = 15.36

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.18) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.