Answer:
11
Step-by-step explanation:
21 + 2 = 23
3 x 4 = 12
23 - 12 = 11
11.
The Multiplication is done first ( by Order of Operations, PEMDAS.):
21 + 2 - 3 * 4
= 21 + 2 - 12
= 23 - 12
= 11.