A class of 50 music students includes 13 who play the piano, 14 who play the guitar, and 8 who play both the piano and the guitar. How many students in the class play neither instrument? ___ Solution n(A U B) = n(A) + n(B) - n(A B) so students who play ateast one instrument is: n(A U B)=13+14-8 n(A U B)=19 so students who donot play any instrument is:50-19=31.