12×35 can be written as 12× ( ___+ 5).
35 can be split as 30 + 5
⇒ 12×35=12×(30+5)=12×30+12×5
(Using Distributive property for multiplication)
If nth term of the series 1 + 5 + 12 + 22 + 35 .........can be written as Tn = an2 + bn + c Find the sum of the 16 terms of the series.