Question

Find the 7th term from the end of AP: 7,10,13,....184

Answer 1

Let us reverse the pattern...
184, .....13, 10, 7
So, the last term,a =184
To find the difference, we take second term minus the first term, d=10-7=3
As, we take the numbers in reverse order, let us take d=-3
So, the 7th planet from the last =a+(n-1)d
= 184+(7-1)(-3)
=184 +6(-3)
= 184 -18
= 166