Question 1177839
Ben paid $45 for an old guitar 

 mark up  price 15% 

He sold it 1.15 *45= 51.75




he used 36% of the money he got for the guitar to buy books 

36 % he spent on books

he spent onbooks 0.36 * 51.75 =18.63

 Ben spent $ 18.63  on books