Answer: 10 students have a cell phone and only 5 of them can use social media
Step-by-step explanation: We see there are 40 students in total and 1/4 OF the class have their own cell phone. The OF means multiplacation so we do 40 X 1/4 which is 10 students who have their cellphone. We then again see 1/2 OF the 10 students can use social media meaning we do 10 X 1/2 which is equal to 5 students out of the 10 can use social media.