In a piggy bank, 40% of the coins are dimes. 3/8 of the remainder are nickels. The remainder is going to be 60% 1/8 of 60% is 7.5%. (just dividing by 8) 3/8 of 60% = 7.5% × 3 = 22.5% are nickels. If 22.5% are nickels, then 77.5% are not. The percentage of coins that aren't nickels is the same as the probability of drawing one because each coin has equal probability to be chosen.