word problem need help

Question

Elsie took all of her cans and bottles from home to the recycling plant. The number of cans was 8 more than 9 times the number of bottles. She earned 10 cents for each bottle and 11 cents for each can, and ended up earning $30.31 in all. 

Answer 1

c= 8+9b

.11c +.10b = 30.31

.11(8+9b) + .10b= 30.31

.88 + .99b + .10b = 30.31

1.09b = 30.31 -.88 = 29.43

b = 29.49/1.09 = about 24.35 for bottles

c = 8 + 9b = 8+ 9(29.49)/1.09 = about 8+9(24.35) = about 233.83 for cans