1.
Let’s
call the number of cookies Cara made “x”
2.
First
she sold three fifths of x (.6x)
3.
The
remaining amount is two fifths of x (.4x)
4.
Then
she one fourth of “two fifths of x” (.25*.4x = .1x)
5.
.6x=.1x+200
6.
.5x=200
7.
x=
400