If 5^21 x 4^11 = 2 x 10^n what is the value of n?
a- 11
b- 21
c- 22
d- 23
e- 32
Answers is B, but I don't remember how to do it.
Thanks
a- 11
b- 21
c- 22
d- 23
e- 32
Answers is B, but I don't remember how to do it.
Thanks












