What is the sum of the integers between the square root of 12 and 40?

1.

the closest perfect squares of 12 are 9 and 16, 

that is 9<12<16

so 




this means,  is  3 point something...

2.

similarly 

36<40<49

so





which means  is 6 point something...

3. 

the sum of the integers between the square root of 12 and 40 is the sum of 4, 5 and 6, since 4 is the smallest integer after root 12, and 6 the greatest integer to before root of 40.

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