1. 1 से 100 के बीच की सम संख्याओ�

1.	1. 1 से 100 के बीच की सम संख्याओं का योग होगा :(a) 2450(b) 2500(c) 2600(d) इनमें कोई नहीं
Answer» To find the sum of even numbers between 1 and 100, we can use the concept sum of n numbers in A.P.(arithmetic progression) Here we need sum of 2,4,6,……..,98(between 1 and 100) Now here First term = 2 difference= 2, n = 50 So now sum of these terms = n/2(2a+(n-1)d) = 49/2(22+(50–1)2) = 49/2(4+(49)2) = 49/2(4+98) = 49/2(102) = 49*51 =2550

1. 1 से 100 के बीच की सम संख्याओं का योग होगा :(a) 2450(b) 2500(c) 2600(d) इनमें कोई नहीं

Answer»

To find the sum of even numbers between 1 and 100, we can use the concept sum of n numbers in A.P.(arithmetic progression)

Here we need sum of 2,4,6,……..,98(between 1 and 100)

Now here First term = 2 difference= 2, n = 50

So now sum of these terms = n/2(2a+(n-1)d)

= 49/2(2*2+(50–1)2)

= 49/2(4+(49)*2)

= 49/2(4+98)

= 49/2(102)

= 49*51

=2550