Question

A bag contains 3 red balls and 4 black balls. A balls is selected at random from the bag, what is the probability that the ball selected be 1) Black 2) red​

Answer 1

Answer:

1)Black - 4/7

2)Red - 3/7

Step-by-step explanation:

Probability = Number of observations

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Total number of outcomes

Data ,

Red balls - 3

Black balls - 4

Total balls - 7

1) P(getting a red ball) = 3/7

2) P(getting a black ball) = 4/7

Answer 2

Answer:

1) 3/7

2) 4/7

Step-by-step explanation:

let black balls be b1, b2, b3 and red balls be r1, r2, r3, r4

Let 's' be the sample space

S={b1, b2, b3, r1,r2,r3,r4}

n(S) =7

Let 'A' be the event 1) black

A={b1, b2, b3}

n(A) =3

p(A) =n(A) /n(S)

=3/7

Let 'B' be the event 2) red

B={r1, r2, r3, r4}

n(B) =4

p(B) =n(B) /n(S)

=4/7