Answer:
1 + (1+6) + (1+6+6) + (1+6+6+6) = 4 × n
Explanation:
The computation of the next line in the sequence is shown below:
As we can see that there is an increase of 6 in the left side and on the right hand side there is an increase of one
So,
1 = 1 × n
1 + (1+6) = 2 × n
1 + (1+6) + (1+6+6) = 3 × n
So, the next line would be
1 + (1+6) + (1+6+6) + (1+6+6+6) = 4 × n
i.e.
1 + 7 + 13 + 19 = 4 × 10
As 1 + 7 + 13 + 19 = 40
And 40 = 4 × 10