Multiple choice

The total of the ages of a class of 60 girls is 900 years. The average age of 20 girls is 12 years and that of the other 20 girls is 16 years. What is the average age of the remaining girls?

  1. 14 years

  2. 15 years

  3. 16 years

  4. 17 years

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Total age=900. First 20 girls: 20×12=240. Second 20 girls: 20×16=320. Remaining 20 girls: 900-(240+320)=340. Average=340/20=17. Option D is correct.