Solveeit Logo
Login

Question

Mathematics Question on Probability

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?

Answer

Total number of marbles = 5 + 8 + 4 = 17

(i) Number of red marbles = 5
Probability  of  getting  a  red  marble=Number  of favourable  outcomesNumber  of  total  possible outcomes\text{Probability}\ \text{ of}\ \text{ getting}\ \text{ a }\ \text{red}\ \text{ marble}=\frac{\text{Number}\ \text{ of} \ \text{favourable}\ \text{ outcomes}}{\text{Number}\ \text{ of }\ \text{total }\ \text{possible} \ \text{outcomes}}
=517=\frac{5}{17}

(ii) Number of white marbles = 8
Probability  of  getting  a  white  marble=Number  of favourable  outcomesNumber  of  total  possible outcomes\text{Probability}\ \text{ of}\ \text{ getting}\ \text{ a }\ \text{white}\ \text{ marble}=\frac{\text{Number}\ \text{ of} \ \text{favourable}\ \text{ outcomes}}{\text{Number}\ \text{ of }\ \text{total }\ \text{possible} \ \text{outcomes}}
=817=\frac{8}{17}

(iii) Number of green marbles = 4
Probability  of  getting  a  green  marble=Number  of favourable  outcomesNumber  of  total  possible outcomes\text{Probability}\ \text{ of}\ \text{ getting}\ \text{ a }\ \text{green}\ \text{ marble}=\frac{\text{Number}\ \text{ of} \ \text{favourable}\ \text{ outcomes}}{\text{Number}\ \text{ of }\ \text{total }\ \text{possible} \ \text{outcomes}}
=417=\frac{4}{17}

Probability of not getting a green marble =1−417=1317=1-\frac{4}{17}=\frac{13}{17}