IF a and b are positive integers divisible by 6 is b the greatest common divisor of a and b ?
A) a=3b+ 6
B) a=3b
Greater common divisior
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given: a and b are both divisible by 6
Stm1: a=3b+6
or (a/3)=b+2
because of this "+2" it is insuff to conclude that b is the gcd of (a,b)
Stm2: a=3b
suff because b will be the gcd of (3b,b) i.e., (a,b)
ans:B
Stm1: a=3b+6
or (a/3)=b+2
because of this "+2" it is insuff to conclude that b is the gcd of (a,b)
Stm2: a=3b
suff because b will be the gcd of (3b,b) i.e., (a,b)
ans:B
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