A piggy bank contains hundred 50 p coins, fifty Rs 1 coins, twenty Rs 2 coins and ten Rs 5 coins. If it is equally likely that one of the coins will fall out when the bank is turned upside down, what is the probability that the coin
(i) Will be a 50 p coin?
(ii) Will not be a Rs.5 coin?
Total number of coins in a piggy bank = 100 + 50 + 20 + 10
= 180
(i) Number of 50 p coins = 100
Probability of getting a $50 \mathrm{pcoin}=\frac{\text { Number of favourable outcomes }}{\text { Number of total possible outcomes }}$
$=\frac{100}{180}=\frac{5}{9}$
(ii) Number of Rs 5 coins $=10$
Probability of getting a Rs 5 coin $=\frac{\text { Number of favourable outcomes }}{\text { Number of total possible outcomes }}$
$=\frac{10}{180}=\frac{1}{18}$
Probability of not getting a Rs 5 coin $=1-\frac{1}{18}$
$=\frac{17}{18}$