Question

The average marks of 10 students of a class is 26, where average marks of passed students is 80 and average marks of failed students is 20. Find the number of students who passed: a) 1 b) 2 c) 3 d) 4

Answer 1

a) 1

let passed students be x

no. of failed students 10-x

average marks of 10 students=80x+20(10-x)/10

this should be=26

80x+20(10-x)/10=26

80x+200-20x=260

60x=260-200

x=60/60

x=1