What are the average marks obtained by all the seven students in Physics ? (rounded off to two digits after decimal)
(a)77.26
(b)89.14
(c)91.37
(d)96.11
(e)103.21
Answer
Answer (as printed): B
Explanation
Total marks obtained in Physics by all the 7 students $$\begin{array}{r} =(90 \% \text { of } 120)+(80 \% \text { of } 120)+(70 \% \text { of } 120) \\ +(80 \% \text { of } 120)+(85 \% \text { of } 120) \\ +(65 \% \text { of } 120)+(50 \% \text { of } 120) \\ =(108+96+84+96+102+78+60)=624 . \end{array}$$ ∴ Average marks obtained by them in Physics $$=\frac{624}{7}=89.14 .$$
Explanation as extracted from the printed page; notation may be imperfect.