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Finding the Third Proportional to 45 and 80

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Solution

The third proportional to 45 and 80 is: 142.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    45 : 80 = 80 : x
  2. Step 2: Convert to fraction form
    45/80 = 80/x
  3. Step 3: Cross multiply
    45x = 80 × 80
  4. Step 4: Simplify right side
    45x = 6,400
  5. Step 5: Solve for x
    x = 6,400/45
  6. Step 6: Final answer
    x = 142.22

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Why These Related Problems?

These problems maintain the same ratio (1.78) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.