if the sum of 7 integers is even, at most how many of these integers could be odd?
a. 3
b. 4
c. 5
d. 6
e. 7
remember that the sum of any 2 odd integers are even
and the sum of 2 evens is even
e.g. 3+5=8 and 4+12=16
but the sum of an even and an odd is odd
e.g. 3+6=9
so can you reason it out?