So we want to know how many out of 1000 people dont listen to any type of the three music types that were surveyed If 30% of people listened to pop, 26% of people listened to rock and 20% of people listened country music. So first lets see how many people liked the three types of music: 30%+26%+20%=76%. So 24% of people didnt like the three types of music that were surveyed. Finally we need to see how many people in 1000 is 24%. 24% out of 1000 people is 0.24*1000=240 people. So 240 people didn't like the 3 types of music.
