Average of ten numbers is calculated. If each number was increased by $12 \%$, then the average
will remain uncharged
may decrease
may increase
increased by $12 \%$
The average of $6$ numbers is $20 .$ If one number is removed, the average becomes $15 .$ What is the number removed?
The average of the test scores of a class of $'m'$ students is $70$ and that of $'n'$ students is $91.$ When the scores of both the classes are combined, the average is $80 .$ What is $n / m$ ?
What is the average of first $7$ multiples of $7\, ?$
A cricketer has a certain average for $10$ innings. In the eleventh inning, he scored $108$ runs, thereby increasing his average by $6$ runs. His new average is
The average of $17$ numbers is $10.9 $ If the average of first nine numbers is $10.5$ and that of the last $9$ numbers is $11.4,$ the middle number is