I think the answer is 6
using the eqn 3n+4 (Let n = 1,2,3,4,5,6,7)
By process of elimination the answer is 6
Ex:
3*1 + 4 = 7
3*2 +4 = 10(Divisible by 5)
3*4 + 4 = 16 (Divisible by 4 and 8)
and so on till u get only 6 remaining
TOOK ME 2 MINS
I need explanation for 1000 PS question
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llewellyn27
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You might also look at it this way: you can divide 3n+3 by 3 (it's equal to 3*(n+1)), so you definitely cannot divide 3n+4 by 3; you'll always get a remainder of 1, because it's one greater than a multiple of 3. If you can't divide 3n+4 by 3, you definitely can't divide it by 6, or any other multiple of 3.
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rsesha
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[quote="babachal"]If n is an integer, which of the following CANNOT be a factor of 3n + 4 ?
(A) 4
(B) 5
(C) 6
(D) 7
(E) 8[/quote]
hi could you please send me a copy of 1000 ps and ds questions. Thanks
(A) 4
(B) 5
(C) 6
(D) 7
(E) 8[/quote]
hi could you please send me a copy of 1000 ps and ds questions. Thanks
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kstv
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n can be odd or even
if odd then n= 2a+1 where a is any no
so 3n + 4 = 6a + 7 when divided by 6 will leave a remainder 1 as 6a is divisible by 6
if even n = 2a
3n +4 = 6a = 4 where it will leave a remainder 1
1 1/2 year old Q
if odd then n= 2a+1 where a is any no
so 3n + 4 = 6a + 7 when divided by 6 will leave a remainder 1 as 6a is divisible by 6
if even n = 2a
3n +4 = 6a = 4 where it will leave a remainder 1
1 1/2 year old Q
