Question

I dont understand how I can solve this one , please can someone provide me with a clear explanation ?

Thank you :)
check the picture below ...

Answer 1

Let the 1st term of an arithmetic sequence is a,

& Common difference = d

Then successive terms will be a + d, a + 2d, a + 3d, …….

nth term = a + (n - 1) d

50th term of the series = 6 + (50 - 1) * 3 = 6 + 49 * 3

= 6 + 147 = 153

Answer 2

Answer:

an=a+(n-1)d

Step-by-step explanation:

a+3d=18

a+11d=50

by solving these two equations

d=4 and a=6

now,99th term=a+98d

6+98(4)=398

hope this helps you