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Finding the Third Proportional to 55.21 and 81.79

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Solution

The third proportional to 55.21 and 81.79 is: 121.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.21 : 81.79 = 81.79 : x
  2. Step 2: Convert to fraction form
    55.21/81.79 = 81.79/x
  3. Step 3: Cross multiply
    55.21x = 81.79 × 81.79
  4. Step 4: Simplify right side
    55.21x = 6,689.77
  5. Step 5: Solve for x
    x = 6,689.77/55.21
  6. Step 6: Final answer
    x = 121.16

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.