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Finding the Third Proportional to 2.18 and 5.21

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Solution

The third proportional to 2.18 and 5.21 is: 12.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.18 : 5.21 = 5.21 : x
  2. Step 2: Convert to fraction form
    2.18/5.21 = 5.21/x
  3. Step 3: Cross multiply
    2.18x = 5.21 × 5.21
  4. Step 4: Simplify right side
    2.18x = 27.18
  5. Step 5: Solve for x
    x = 27.18/2.18
  6. Step 6: Final answer
    x = 12.48

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Why These Related Problems?

These problems maintain the same ratio (2.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.