25% decrease.
first let’s find how many have stayed. to do this, you will do,
15
—
20
which can be simplified to
3
—
4
because both can be divided by 5. but these are the people that stayed, were trying to find how many left. so, we will resort to our left over
1
—
4
which, in decimal form, is 0.25.
so, the squads size decreased by 25%
:)
