Question

What is the sum of all of the odd numbers from 21 to 39?

Answer 1

heya friend here's ur answer⬇⬇⬇⬇
________________

The odd numbers between 21 to 39 are

21,23,25,27,29,31,33,35,37,39

now,
add these numbers 21+23+25+27+29+31+33+35+37+39

the result would come 300.
_________

hope it helps :-)

#thankyou....

Answer 2

we know
n=10
a=21
d=2
s=n/2[2a+(n-1)d]
s=10/2[2×21+(9)2]
s=5[42+18]
s=5[60]
s=300