Question

A bag contains 2 red,3 green and 2 blue balls two balls are drawn at random . What is the probability that none of the balls drawn is blue

Answer 1

❤hello mate ❤

here's the answer

total no of chances to draw 2 balls at random from 7coloured balls,n(s)=7C2=21

let E be an event to draw 2 balls other than blue .

no of chances to draw two balls other than blue are,n(E)=2C2+3C2+2C1.3C1=1+3+6=10

the probability that none of balls drawn is blue is,p(E)=n(E)/n(s)=10/21

or

Total number of balls = (2 + 3 + 2) = 7.

n(S)= Number of ways of drawing 2 balls out of 7  = 7C2 `=21

Let E = Event of drawing 2 balls, none of which is blue.

n(E)= Number of ways of drawing 2 balls out of (2 + 3) balls.= 5C2=10

so,probability=10/21

Answer 2

Answer:

9/21

Step-by-step explanation:

1) 2c1x3c1 = one red ball & one green ball;

2) 2c2  = both are red balls.

3) 3c2 = both are green balls,

7c2 = total probability.

(2c1x3c1) + 2c2 + 3c2 /7c2;

5+1+3 / 21;

9/21;