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Finding the Third Proportional to 21.09 and 27.75

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Solution

The third proportional to 21.09 and 27.75 is: 36.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    21.09 : 27.75 = 27.75 : x
  2. Step 2: Convert to fraction form
    21.09/27.75 = 27.75/x
  3. Step 3: Cross multiply
    21.09x = 27.75 × 27.75
  4. Step 4: Simplify right side
    21.09x = 770.06
  5. Step 5: Solve for x
    x = 770.06/21.09
  6. Step 6: Final answer
    x = 36.51

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Why These Related Problems?

These problems maintain the same ratio (1.32) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.