If x is a positive integer,is the remainder 0 when [3^x +1]/10?
1. x= 3n + 2 ,n is a positive integer
2. x>4
OA D
1. x= 3n + 2 ,n is a positive integer
2. x>4
OA D
dont understand how can OA be D (i might be wrong... so plz help me understand the OA)
stmt 1:
x= 3n + 2 ,n is a positive integer
for remainder to be 0 when [(3^x+1)/10], 3^x should result in number which has unit as 9.
and for 3^x=9..729..59049 x should be equal to 2,6,10,14,....etc
from 3n+2 we can get x=14 if n=4....but not when n=1,2... so insufficient
stmt 2:
x>4
as said in stmt 1 x needs to be 2,6,10...etc which can be true from stmt 2 but not convincingly becoz x can be 7,8,9....etc or can be 10,14,...etc
so insufficient
So IMO:E
