Ok today in class we learned how to take a number and make it binary, no big, but to take a random binary and make it back to a number....whoa...

This i can do:

85 to binary:

\ = divide

85 \ 2 = 42.5 1

42 \ 2 = 21 0

21 \ 2 = 10.5 1

10 \ 2 = 5 0

5 \ 2 = 2.5 1

2 \ 2 = 1 1

1 \ 2 = 1 1

So 85 in binary is 1110101

but to take say 101011010(random) and make it a regular number, i'm lost, any help?