GMAT Prep URGENT!!!

[Stendulkar]

What is the remainder when +ve integer x is divided by 3 ?

1) x divided by 6 gives a remainder as 2
2) x divided by 15 gives a remainder as 2

[MAAJ]

What is the remainder when +ve integer x is divided by 3 ?

1) x divided by 6 gives a remainder of 2
x = 6q + 2
x = (3*2)q + 2
x = 3(2q) + 2
When x is divided by 3, the remainder is 2, but the quotiend must be doubled. Sufficient

8 = 6(1) + 2 -> 8 = 3(2) + 2
20 = 6(3) + 2 + -> 20 = 3(6) + 2

2) x divided by 15 gives a remainder of 2
x = 15q + 2
x = (3*5)q + 2
x = 3(5q) + 2
When x is divided by 3, the remainder is 2, but the quotiend must increase by a factor of 5. Sufficient

17 = 15(1) + 2 -> If 17 = 3(5) + 2
47 = 15(3) + 2 -> If 47 = 3(15) + 2

Correct Answer [spoiler](D)[/spoiler]

[vineeshp]

OA D.

1) Translates to: The numbers satisfying the condition are 2, 8, 14 etc. Remainder will be 2 when divided by 3.
2) The numbers satisfying the condition are 2, 17, 32 etc. Remainder will be 2 when divided by 3.


---------
Mathematically,

A number which gives a remainder n when divided by 6 will give same remainder when divided by 3 too. Same holds for 15 as well.