Following are the marks obtained by 25 students in economics. Find out the mean marks by using Direct and Short-cut Method. {:("Marks",10,20,30,40,50,60),("Number of Students",5,2,3,8,4,3):}

Following are the marks obtained by 25 students in economics. Find ou

1.	Following are the marks obtained by 25 students in economics. Find out the mean marks by using Direct and Short-cut Method. {:("Marks",10,20,30,40,50,60),("Number of Students",5,2,3,8,4,3):}
Answer» Solution :Direct Method: `barX=(sum FX)/(sum f)` `barX=(880)/25=35.2` Mean Marks of 25 Students inEconomics = 35.2. Short-cut Method: `barX=A+(sumfd)/(sumf)` `=40+(-120)/25=40-(120)/25` `=40-4.8=35.2` Thus, Mean Marks= 35.2.