Topic: Engineering Mathematics
A bag contains eight white and six red marbles. The probability of drawing two marbles of same colour is-
- A. $\frac{^{8}C_{2}\cdot^{6}C_{2}}{^{14}C_{2}}$
- B. $\frac{^{8}C_{2}}{^{14}C_{2}}+\frac{^{6}C_{2}}{^{14}C_{2}}$
- C. $\frac{^{8}C_{2}\cdot^{6}C_{2}}{^{14}C_{2}\cdot^{14}C_{2}}$
- D. $\frac{^{8}C_{2}}{^{44}C_{2}}+\frac{^{6}C_{2}}{^{12}C_{2}}$
Answer: B. $\frac{^{8}C_{2}}{^{14}C_{2}}+\frac{^{6}C_{2}}{^{14}C_{2}}$
Explanation: Total marbles = 8W + 6R = 14. Probability of drawing two marbles of same colour = P(Both White) + P(Both Red) = $\frac{^{8}C_{2}}{^{14}C_{2}}+\frac{^{6}C_{2}}{^{14}C_{2}}$.