See attached for the work
First you solve the brackets;
68+7 = 75
Then you add the 93;
75+93 = 168
3 is how many wool you need for 8 caps because each cap uses 0.5 wool so add it all up or like multiplication so 0.5 X 8 = 4 0.5 X 6 = 3
To be honest I do not know I am not that great at math but I can try
1 is really b, I just learned this
2 is really a