R. Gupta Solutions for Chapter: Average, Exercise 1: EXERCISE

The average of $6$observations is $12$. A new seventh observation is included and the new average is decreased by $1$. The seventh observation is:

A man whose bowling average is $12.4$takes $5$wickets for $26$runs and thereby decreases his average by $0.4$. The number of wickets, taken by him, before his last match, is:

The average of marks obtained by $120$candidates was $35$. If the average of marks of passed candidates was $39$and that of failed candidates was $15$, the number of candidates who passed the examination is:

Out of three numbers, the first is twice the second and is half of the third. If the average of the three numbers is $56$, the three numbers in order are:

Out of four numbers, the average of first three is $15$and that of the last three is $16$. If the last number is $19$, the first is:

The average age of $A, B, C$ and$D$  five years ago was $45$years. By including $X$, the present age of all the five is $49$years. The present age of $X$is:

The average expenditure of a man for the first five months is $\mathrm{Rs}.120$ and for the next seven months it is $\mathrm{Rs}.130.$ If he saves $\mathrm{Rs}.290$ in that year, his monthly average income is:

If $a, b, c, d, e$ are five consecutive odd numbers their average is