Question

1+3+5+7.....+69= X then the value of X is what​

Answer 1

Heya mate here is your answer:

✍Let us find the total number of terms:-

a = 1 and d = 2

a + (n - 1) d = 69

1 + 2n - 2 = 69

2n = 70

n = 35 terms.

✍Now,

X = 35/2 {2 + ( n- 1) d}

2X=( 2 + 2n - 2)×35

2X= 2 × 35 × 35

X = 1225