Question

there are 3 second grade classes at the sunshine school one has 22students and another has 20 students if there are 63 students in the whole second grade how many are in the third class

Answer 1

 there would be 21 in the last class

Answer 2

u have to add 22+20 = 42 and subtract(-) 63-42 = 21 and 21 is ur answer