Question

find the Sum of natural numbers between 1 and 140
here , a=4, d=4 ,tn=136​

Answer 1

Answer:

From 1 to 140, natural numbers divisible by 4 are 4, 8, ... 136. Thus, number of terms (n) = 34.

Step-by-step explanation:

this can help you

Answer 2

Answer:

4

Step-by-step explanation:

,

140 = a+(n-1)d

140 = 4+(n-1)4

136 = (n-1)4

34 = (n-1)

35 = n

So there are 35 terms in this ap.

Now sum of an ap is given by :-

n/2{2a+(n-1)d}

n/2 {(a) + (a+(n-1)d)}

35/2 {4 + 140}

35/2 (144)

35 × 72

2520 (Answer)

Hope this helps.