Add from rightmost place value. Regroup when a column totals 10 or more.

Hundredths	=	5 + 8 = 13 hundredths = 1 tenth + 3 hundredths
Tenths	=	5 + 1 + 1 (carry) = 7 tenths
Ones	=	3 + 2 = 5
Sum	=	5.73