Is the sum of integers a and b divisible by 7?
1) a is not divisible by 7
2) a-b is divisible by 7
????
1) a is not divisible by 7
2) a-b is divisible by 7
????
1) a is not divisible by 7
Cannot determine. Since we dont know b.
2) a - b is divisible by 7
In this case, taking examples --
18 - 4 divisible by 7, but 18 + 4 not divisible by 7
10 - 3 divisible by 7, but 10 + 3 not divisible by 7
7 - 0 divisible by 7, but 7 + 0 divisible by 7
3) Taking both stmt together -
we can drop out 7 - 0, since 7 is divisible by 7.
Thus we can conclude that a + b is not divisible by 7
Hence C
I chose C
OA please.
