Answer:
13, if 28 cats & dogs
Step-by-step explanation:
let c be the no. of cats and d be the no. of dogs
5.50c + 8d = 191.50
Notice that the sum is in 0.5, which is only possible when c is odd.
Try different combinations of c being odd and check which one gives d as a whole number, using
d = (191.50-5.50c)/8
c = 1, d = [191.50-5.50(1)]/8
d = 23.25 (not possible)
c = 3, d = [191.50-5.50(3)]/8
d = 21.875 (not possible)
c = 5, d = [191.50-5.50(5)]/8
d = 20.5 (not possible)
c = 7, d = [191.50-5.50(7)]/8
d = 19.125 (not possible)
c = 9, d = [191.50-5.50(9)]/8
d = 17.75 (not possible)
c = 11, d = [191.50-5.50(11)]/8
d = 16.375 (not possible)
c = 13, d = [191.50-5.50(13)]/8
d = 15 (possible)
So c = 13 and d = 15
