Pratham Ashish
Last Activity: 15 Years ago
Dear Naveen
for a no to be divisible by 3 , possibilities are 3,6,9,15,18,21
if 2 no. are x and y , den
eqns are
x + y = 3 ,x + y = 6, x + y = 9, x + y = 12 , x + y = 15 , x + y = 18 , x + y = 21
for 1st eqn x,y wud be 1 & 2
for 2nd set is (2,4),(1,5)
for 3rd (1,8),(2,7),(3,6),(4,5)
for 4th (1,11),(2,10),(3,9),(4,8),(5,7),(6,6)
for 5th (12,3),(11,4),(9,6),(10,5),(8,7)
for 6th (12,6),(11,7),(10,8)
for 7th (10,11)
just count the possibility and dat is ur ans