Question

18. 80 bulbs are selected at random from a lot and their
life time (in hours) recorded in the form of frequency
table is given below:
Lifetime (in hours) 300 500 700 900 1000
Frequency
10 12 23 25 10
Find the probability that bulb selected randomly
from the lot has lifetime less than 900 hours.​

Answer 1

Answer:

Step-by-step explanation:

Total number of bulbs=80

Number of favourable outcomes=10+12+23

=55

P(bulbs with lifetime less than 900 hours)=number of favourable outcomes/total number of outcomes

=55/80=11/16

Answer 2

Answer:

Step-by-step explanation:

Total number of bulbs = 80

Number of favourable outcomes = 10+12+23=45

P( bulbs with lifetime less than 900 hrs)

Number of favourable outcomes / total number of outcomes

= 45/80

= 9/16