What is the greatest possible common divisor of two different positive integers, each less than 213, if neither of them is even?
A. 69
B. 71
C. 105
D. 207
E. 209
to find greatest possibile HCF
Best way to solve is to try each answer....
A. 69 ---- given number is already high, to get the second number, we try to check by multiplying by 2, or 3
Possible Numbers = 138, 207.
Possible pair of Numbers - {69, 138} , {69,207} , {138, 207}
Correct pair without even number
{69,207} (Answer)B. 71 ----------------to find possible answer on multiply by 2.
Possible Numbers = 142, 213.
No possible pair. (either even or equal to 213)
C. 105 ------------to find possible answer on multiply by 2.
Possible Numbers = 210, 315
No possible pair. (either even or grater than 213)
D. 207 --------
Possible pair = 414
All further numbers will be greater than 213.