#### Question

Fill up the boxes and find out the number of terms in the A.P.

1,3,5,....,149 .

Here a = 1 , d =b`[ ], t_n = 149`

t_{n} = a + (n-1) d

∴ 149 =`[ ] ∴149 = 2n - [ ]`

∴ n =`[ ]`

#### Solution

In the A.P. 1,3,5,....,149

a = 1 , d = 2 , t_{n} = 149

t_{n} = a + (n-1)d

149 = 1+ (n-1) × 2

149 = 1 + 2n -2

149 = 2n - 1

∴ 2n = 150

∴ n = 75

Is there an error in this question or solution?

Solution Fill up the Boxes and Find Out the Number of Terms in the A.P.1,3,5,....,149 .Here a = 1 , D =B`[ ], T_N = 149`Tn = a + (N-1) D ∴ 149 =`[ ] ∴149 = 2n - [ ]`∴ N =`[ ]` Concept: Sum of First n Terms of an AP.