Solution :
It is given that Little Snail is going to visit one of his friend at the pond which is 3 miles away.
When the snail crawls 1/2 of a mile per day, it will take him, 
= 6 days to get to the next pond.
When the snail crawls 1/3 of a mile per day, it will take him, 
= 9 days to get to the next pond.
When the snail crawls 1/4 of a mile per day, it will take him, 
= 12 days to get to the next pond.
When the snail crawls 3/4 of a mile per day, it will take him, 
= 4 days to get to the next pond.
When the snail crawls 2/3 of a mile per day, it will take him, 
= 4.5 days to get to the next pond.