Find the sum of all odd numbers up to 100. Options
A) 2500	B) 2400	C) 2300	D) 2200	E) 2100
The given numbers are 1, 3, 5, 7, ..., 99.   This is an A.P. with a = 1 and d = 2.   Let it contain n terms. Then,   1 + (n - 1) x 2 = 99 or n = 50.   Required sum = n/2 (first term + last term)   = 50/2 (1 + 99) = 2500.   2500nswer is 2500.
<result>A</result>
Find the sum of all odd numbers up to 100.