The mean of marks secured by 45 students in division A of class X is 56, 40 students of division B is 52 and that of 40 students of division C is 50. Find the mean of marks of the students of three divisions of Class X.
In the following question, some part of the sentence may have errors. Find out which part of the sentence has an error and select the appropriate option. If a sentence is free from error, select 'No Error'.
They will (A)/ leave the office at six and (B)/ reach at home by seven. (C)/ No error (D)