a boy perform 5 times a reaction and his reading are 2,2.1,2,2.2 but unfortunately
5th reading clearly not visible because a drop of chemical fall onto it.but luckily he
have mean of all reading which is 2.please help him in finding 5th reading.	Pick
A) 2  B) 1.7  C) 1.9  D) 1.8  E) 2.1

Rationale: solution let 5 th reading be x ( 2 + 2.1 + 2 + 2.2 + x ) / 5 = 2 8.3 + x = 10 x = 1.7 answer b
Answer: B