If one cat eats 1/4 of a tin per day then two cats eat 1/2 of a tin per day.
We have 9 tins so if each day cats eat 1/2 we have to divide 9 with 1/2 and we get 18 which is for how many days she can feed the cats until she runs out of food.
Hope this helps.
58-13=45 45/9=5 Carlos rented the bike for 5 hours