find the sum of all two digit odd number
Answers
Answered by
1
Answer:
2475
Step-by-step explanation:
All two-digit odd positive numbers are 11, 13, 15, 17, ...., 99. which are in AP with a=11,d=2,l=99
Let the number of terms be n.
a
n
=99
a+(n−1)d=99
11+(n−1)×2=99
n=45
Sum of n terms is given by
S
n
=
2
n
(a+l)
S
n
=
2
45
(11+99)=2475
Therefore, the sum of all two-digit odd positive numbers is 2475.
Answered by
0
Answer:
2475
Step-by-step explanation:
11+13+15+17+19+21+23+25+27+29+31+33+35+37+39+41+43+45+47+49+51+53+55+57+59+61+63+65+67+69+71+73+75+77+79+81+83+85+87+89+91+93+95+97+99=2475
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