3 Tutor System
Starting just at 265/hour

# A box contains 5 red marbles, 8 white marbles and 4 green marbles. One marble is taken out of the box at random. What is the probability that the marble taken out will be (i) red? (ii) white? (iii) not green?

Total number of marbles in the box = 5 (Red) + 8 (White) + 4 (Green) = 17

$$\therefore$$ Total number of elementary events = 17

(i) There are 5 red marbles in the box

$$\therefore$$ Favourable number of elementary events = 5

Hence, P (getting a red marble) $$= \ \frac{5}{17}$$

(ii) There are 8 white marbles in the box.

$$\therefore$$ Favourable number of elementary events = 8

Hence, P (getting a white marble) $$= \ \frac{8}{17}$$

(iii) There are 5 + 8 = 13 marbles which are not green in the box.

$$\therefore$$ Favourable number of elementary events = 13

Hence, P (not getting a green marble) $$= \ \frac{13}{17}$$