Question

Let us assume that a student is chosen from a random
sample of 80 students, out of which 30 have opted for
Maths, 20 opted for Physics, and 10 have opted for both
Maths and Physics. Find the probability that the student
has opted for either Maths or

Physics.​

Answer 1

Answer:

1/2

Step-by-step explanation:

n(m U p)=n(m) + n(p)- n(m n p)

= 30+20-10

=40

n(mUp) 40 1

p(m U p) = _______ = ___ = ___

Total 80 2

Answer 2

Answer:

the answer is 1/2 (while assuming by default that the students opting for both maths and physics are(common) among those who have either opted for physics or maths i.e a separate section for "both maths and physics" students is NOT set up)

Step-by-step explanation:

the answer is 1/2 (while assuming by default that the students opting for both maths and physics are(common) among those who have either opted for physics or maths i.e a separate section for "both maths and physics" students is NOT set up)

Step-by-step explanation:

total number of students with only maths= 30

total number of students with only physics=20

total number of student with either maths or physics= 30+20=50

BUT

10 students of BOTH MATHS AND PHYSICS are common to them so they need to be excluded;

hence net total number of students with either maths or physics=50-10=40

hence the probability of the students having either maths or physics = 40/80 =1/2=0.5

hope it helps

inayat abbas malla