Find the n<sup>th</sup> term of the following sequence :</br> 5 + 55 + 555 + . . . . T<sub>n<…

The sum of the first 16 terms of an AP whose first term and third term are 5 and 15 respectively is

The sum of first five multiples of 3 is:

How many 2-digit positive integers are divisible by 4 or 9?

If an A.P. has a = 1, t<sub>n</sub> = 20 and s<sub>n</sub> = 399, then value of n is :

The 3<sup>rd</sup> and 7<sup>th</sup> term of an arithmetic progression are -9 and 11 respective…

(1) + (1 + 1) + (1 + 1 + 1) + ....... + (1 + 1 + 1 + ...... n - 1 times) = ......

If 7<sup>th</sup> and 13<sup>th</sup> terms of an A.P. be 34 and 64 respectively, then its 18&lt…