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Finding the Third Proportional to 7.80 and 17.61

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Solution

The third proportional to 7.80 and 17.61 is: 39.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    7.80 : 17.61 = 17.61 : x
  2. Step 2: Convert to fraction form
    7.80/17.61 = 17.61/x
  3. Step 3: Cross multiply
    7.80x = 17.61 × 17.61
  4. Step 4: Simplify right side
    7.80x = 310.23
  5. Step 5: Solve for x
    x = 310.23/7.80
  6. Step 6: Final answer
    x = 39.75

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Why These Related Problems?

These problems maintain the same ratio (2.26) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.