2+2=

4

In decimal (base-10), 2 + 2 = 4. If you’re studying different bases: in base-3, 2 + 2 = 11; in base-b with b > 4, 2 + 2 = 4; in binary terms, 10 + 10 = 100 (which is 4 in decimal). Want a quick base-conversion exercise?