Question

I want step by step solution ​

Answer 1

Answer:

Option (3)

Step-by-step explanation:

Favourable outcomes = < 70 marks.

i.e.,

Total no. of favourable outcomes :

→ No. of students obtaining marks, 30-40 + No. of students obtaining marks, 40-50 + No. of students obtaining marks, 50-60 + No. of students obtaining marks, 60-70.

→ 12+25+10+8

→ 55.

Total no. of outcomes :

→ Total no. of students

→ 70. (which is already given in question)

Now,

Probability = (Total no. of favourable outcomes) ÷ (Total no. of outcomes)

= 55/70

= 11/14