Question

Most likely to questions because they are very short will take a picture of it

Answer 1

In this question, we are dealing with an arithemetic progression

1,4,7,10,.....

a(first term )=1

d(common difference) = 4-1 =3 or 7-4=3

d=3

n=30

`S=(n)/(2)(2a+(n-1)d)`
`\begin{gathered} S=(30)/(2)((2*1)+(30-1)3) \\ \text{ =15(2+(29}*3)) \\ \text{ =15(2+87)} \\ \text{ =15(89)} \\ \text{ =1335} \end{gathered}`

The sum of the first 30 terms is 1335.