Question

If 7 times the 7th term of an AP is equal to 11 times its 11th term, find
the 18th term of the AP.

Answer 1

what is AP?

Answer 2

the 'n'th term of AP is given by \(T_n=a+(n-1)d\)
where a is first term and d is common difference.
to find 18th term u just need to find a and d.
can u first right the expression for 7th and 11th term??

Answer 3

@chihiroasleaf for details on AP,GP and HP, u can look here:
http://openstudy.com/study#/updates/503bb2a0e4b007f9003103b0

Answer 4

@Hamidul any more information is given??
otherwise the answer will be in terms of 'd'.

Answer 5

ahh..., Arithmetic Progression..., I'm not used to use that abbreviation... :D
thanks @hartnn