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Finding the Third Proportional to 2.80 and 5.61

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Solution

The third proportional to 2.80 and 5.61 is: 11.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.80 : 5.61 = 5.61 : x
  2. Step 2: Convert to fraction form
    2.80/5.61 = 5.61/x
  3. Step 3: Cross multiply
    2.80x = 5.61 × 5.61
  4. Step 4: Simplify right side
    2.80x = 31.43
  5. Step 5: Solve for x
    x = 31.43/2.80
  6. Step 6: Final answer
    x = 11.21

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Why These Related Problems?

These problems maintain the same ratio (2) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.