MAHARASHTRA Class 10: Word Problems on A.P. Videos | Word Problems of A.P.

Leta = first term and d = common difference of the given AP.

Here, in an AP consisting of 11 terms, , i.e.the 6^th term, is the middle term.

Given: middle term = 30

∴ a + 5d = 30 … (i)

We know  

Here, the n^th term = 20.75

a = 5, d = 1.75

We know that,

a_n = a + (n - 1)d

∴ 20.75 = 5 + (n - 1) × 1.75

∴ (n - 1) = 15.75 ÷ 1.75 = 9

∴ n = 9 + 1 = 10