If a*b*c=60, where a, b, and c are integers greater than 1, a+b+c=?
(1) a+b=8
(2) Both a and b are odd numbers.
the answer says B .why cant it be D coz a ,b , & c can be 3 , 5 , & 4
as per statement 1 - a+ b : 3 + 5 = 8
can anyone help with this .
please help
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a,b,c could be 2,6,5 also .... thats why A is not suff.anjaligeorge1 wrote:If a*b*c=60, where a, b, and c are integers greater than 1, a+b+c=?
(1) a+b=8
(2) Both a and b are odd numbers.
the answer says B .why cant it be D coz a ,b , & c can be 3 , 5 , & 4
as per statement 1 - a+ b : 3 + 5 = 8
can anyone help with this .
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An other way of solving this is, we know that the prime factors of 60 = 2 x 2 x 3 x 5. Considering statement 1, a+ b = even , so a and b must be odd or a and b must be even. So a and b can 5 and 3 if odd, or they can 2 and 6 when considering even. So we know a+b+c can vary and is INSUFF.
Statement 2: clearly says a and b are odd and the two of the prime factors are odd as well3, 5). The other number C can only be 4. So there is only one value of a+b+c.
Statement 2: clearly says a and b are odd and the two of the prime factors are odd as well3, 5). The other number C can only be 4. So there is only one value of a+b+c.