11x represents the fiction
X represents the nonfiction book
11x+x=312
12x=312
Divide both by 12
X=26
To find the fiction you have to do 11 times 26
11•26=286
To check the answer you add 286 and 26
If it adds up to 312 the answer is correct
1. 1/3
2.1/3
3.3/36
this is because probability is equal to favourable outcome/total outcome. in this case, favourable outcome is the outcome that is asked in the question and total outcome is all the possibilities