Answer:
81/450 or 18%
Explanation:
Since you are trying to get the probability model for the chance silver will be selected, you add up 81,117 and 252. This gets you 450denominator and since you are trying to find the probability for sliver, you put 81 in the numerator. This gets the you fraction 81/450. If you divide it, you get 0.18. Now if you are trying to make a decimal into a percent, you move the decimal point two spots to the right. So, 0.18 becomes 18%.