1 + 2 + 3 +………+ 50 equals

12 numbers are in arithmetic progression. Average of first and last number of this progression is 16. What is the average of these 12 numbers?

6 + 12 + 18 + 24 + ....... +612 = ?

All pillars of street light was installed in a straight line at a distance of 50 meter(m) interval. What will be the distance between first and ninth pillar ?

Find the sum of all three-digit numbers divisible by 9 .

On simplification 1 – 2 + 3 – 4 + 5 – 6 - - - - + 101, we get

1 + 2 + 3 +………+ 50 equals

If in an A.P., the pᵗʰ term is q and the (p + q)ᵗʰ term is 0, then the qᵗʰ term is:

If in an A.P., Sₙ = qn² and Sₘ = qm², where Sᵣ denotes the sum of first r terms of the A.P., then $$S_q$$​ equals:

The first term and last term of an AP are 33 and -57 respectively. If there are 16 terms in the series, then what will be sum?

Sum of p terms of AP is q and sum of q terms of AP is p. Common difference of A.P. is: