It will take little snail 12 days to reach his grandma:if 1/2 a mile equals a day just count up taking score or tally on paper a make mental note.Another way to do it is to thinks that 1/2 a mile equals a day so 1 mile equals 2 days then just add 2, 2=1,4=2,6=3,8=4,10=5,12=6.