Question

if a + b are odd integers which of the following must be an even integer:

(a+b)/2

ab-1

(ab+1)/2

Answer 1

try values and find solution

Answer 2

if a + b is odd then a is odd and b is even

Answer 3

so a.b is even

Answer 4

so a.b -1 is odd

Answer 5

thank you very much :) though on the answer sheet ab-1 is even...must be a mistake...

Answer 6

yes it's wired

Answer 7

it's none of that options

Answer 8

the sum a+b is odd or individual no are odd?

Answer 9

that's where i'm confused bcz the Q says If a + b are odd integers....

Answer 10

if it's individual a+ b is even

Answer 11

a.b is odd

Answer 12

a.b-1 is even

Answer 13

mmm.....the 3rd seems the only possible answer

Answer 14

how?

Answer 15

Nevermind, B is the only possible answer. ab is odd for odd a,b therefore ab - 1 must be even.

Answer 16

I tried it's giving odd...

Answer 17

let's assume a+b is 5 ..........so ab is 4x1???

Answer 18

how is ab odd?