what is the 10th,20th,and 30th terms of
1.)3,14,25,36,47
2.)25,38,51,64,77
I'll just find the 10th term of 1.) The others are done the same way.
Use the formula
an = a1 + (n-1)·d
You have a1 = 3, and n = 10. But you also need d.
To find d you subtract the 1st term from the 2nd term:
d = a2 - a1 = 14 - 3 = 11
But you should also check to make sure that the sequence is arithmetic,
otherwise the formula would not work:
d = a3 - a2 = 25 - 14 = 11
d = a4 - a3 = 36 - 25 = 11
d = a5 - a4 = 47 - 36 = 11
If any of those had been different, the above formula would not work.
But since they're all the same it will work.
For the 10th term,
an = a1 + (n-1)·d
a10 = 3 + (10-1)·11
an = 3 + (9)·11
an = 3 + 99
an = 102
You can find all the others exactly the same way.
Edwin