Question

a bag contains 3white and 4red balls.two draws of one ball each are made without replacement.what is the probability that one is red and other is white

Answer 1

Probability one is red of the first draw is 4/7
Probability one is white of the 2nd draw is 3/6 =1/2
multiply of both up, we get 4/7 * 1/2 = 4/14 = 2/7

Answer 2

does that make sense, @pooja123 ?

Answer 3

the answer is 4/7.

Answer 4

4/7 is just for the probalility of one red only :)
do u want draw 2 balls, right ?

Answer 5

yes they used the formula like 2into4into3/7into 6

Answer 6

hmm. i dont understand that, actually the formula to get the probability of an event using : P(A) = number of event A / number all event

Answer 7

hmm well she is right the answer would be 4/7

Answer 8

why, can u explain more, nubber ?

Answer 9

we found the probability 2/7 when first red and second white
so P[RW] = 2/7
this is one case another possibility is that first is white and second is red
P[WR] = 3/7 * 4/6 = 2/7
so total probability of this event = p[WR]+p[RW]

Answer 10

thanks

Answer 11

wait, is draw it one by one Or 2 balls direct ?

Answer 12

hmm i think one by one...

Answer 13

hmmmm.. yeah, i see now. the question doesnt says the the first draw must red or white, thanks for your corrections @nubeer and sorry for @pooja123 :)

Answer 14

glad to help :)

Answer 15

thank u guys

Answer 16

im not becareful with this question :)

Answer 17

k

Answer 18

can u see my isosceles triangle solution for one sec