1/8 of a small box of detergent cleans 1 load of laundry. How many loads could you wash with 5 boxes of detergent?

I need to round numbers but i do not know which ones to round.

1/8 box will do 1 load,

so 1 box will do 8 loads
and thus 5 boxes will do 40 loads

Don't know where rounding would enter the picture here.