Melissa did 10 math problems on 3 different days and she did 20 problems on 2 other days. How many problems did she complete in all? Choose the expression that is a correct translation of the problem. (3 x 2) + (10 x 20)
(3 x 2) x (10 x 20)
(3 x 10) + (2 x 20)
(3 + 2) + (10 + 20)