Joe bought only twenty cent stamps and thirty cent stamps. How many twenty cent stamps did he buy?
(1) Joe bought more than 8 twenty cent stamps.
(2) Joe bought a total of $2.50 worth of stamps.
The OA says C but I am getting B ..guys can you please explain
I applied my reasoning that .2x+.3y=2.50
Hence we add and we can get 2.50 ..so B should be sufficient..I tried but there are no other integer choices for this combination.
Please help ....
1--> no suff.
2--> .20x+ .30y= 2.5 muliple by 5 to remove clumsy.
1x +1.5y= 12.5 ---> now if x= 11 then y=1 or if x= 6 then y= 5 and similar way you could get different count for 20 cent stamps.
now 1+2 --> from one we got more than 8 hence it must be suff cuz, if x= 9 or 10 , you wont get proper value for y as y should be an integer.
Hence 11 - 20 cents stamps