A pet store had thirty-one siamese cats and forty-nine house cats. During a sale they sold sixty-one cats. How many cats do they have left?

19

Step-by-step explanation:

31 + 49 = 80

80 - 61 = 19

Yes. 
First we need to find out what the number of the rest of the class is. 24-13 is 11. So since 13 kids sold 150 each, we would need to multiply them, that would give us 1950. Then we need to find out the total of the 11 kids that sold 60 each. 60 times 11 is 660. Then we need to add 1950 and 660. That gives us 2610 tickets. That is more than 2000, so they reach their goal.