GMAT PREP DIVISIBILTY ?

[dferm]

PLEASE ELABORATE

[ri2007]

The ans is A

When 4 is divided by 3 remainder is 1

when 7n is divided by 3 remainder = 2 (this u can find by plugging values of n where n + 1 is divisible by 3. Also since it is given that n is a positive integer and n+1 is divisible by 3 u can rule out the possibility of n being 0)

So remainder when 4+ 7n is divided by 3 = 1+2 = 3 and since 3 is divisible by 3, 4 + 7n is a multiple of 3

Statement 2 just gives that n > 20

so n can be 21 and 21+4 = 25 so remander = 1
or n can be 26 and 26 + 4 = 30 and remainder = 0

dferm
if possible can u pls add the attachements as photos. Downloading this in the form u have attached is too time consuming, or may be am having internet problems)

Any way, in case u do not get reply from any one else, will try downloading and positing tomorrow.