Hi I am really stuck with my home work. Please help.

the question is A boy watched aconvoy of 10 identical snails cross asmall path and measured the time the whole process took. It took exactly 50 minutes. This was the time taken when the first snail came on the path until the last left the path. The snails travelled nose to tail in asingle file and the path could only accomodate 8 snails at any one time. the snails travelled at the same speed and each snail was on the path for the same time. For how long was each snail on the path.

My sister says less than 50 minutes I do not agree. Please help.