65%=0.65
So do 160*0.65 to get 104.
You were right, but this way is far easier.
Write your string of equation in the form:
problem
65%*160=some expression
=
= some expression
What I have done
.50*160=80
16*6=96
96+8=104
for 160 (10*16)
for 16 (16/2=8)
However, I'm not sure if i have done this right because I have followed the book...