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Finding the Third Proportional to 13.78 and 21.30

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Solution

The third proportional to 13.78 and 21.30 is: 32.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    13.78 : 21.30 = 21.30 : x
  2. Step 2: Convert to fraction form
    13.78/21.30 = 21.30/x
  3. Step 3: Cross multiply
    13.78x = 21.30 × 21.30
  4. Step 4: Simplify right side
    13.78x = 453.56
  5. Step 5: Solve for x
    x = 453.56/13.78
  6. Step 6: Final answer
    x = 32.91

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Why These Related Problems?

These problems maintain the same ratio (1.55) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.