I believe the answer to this one is E. We can write the expression P/(Q*R) as P/Q*1/R or P/R*1/Q
(1) we can substitute P/Q=3 Then the expression becomes 3*1/R. picking different values for R. if R=2, then the expression 3*1/2=3/2 a non-integer. However, if R=1 then 3*1/1=3 is an integer. therefore, (1) is insifficient.
(2)Again P/(Q*R)=P/Q*1/R. If P/Q=2 then we should pick different numbers for 2*1/R. if R=2, 2*1/2=1 which is an integer. However if R=3, 2*1/3=2/3 is not So, (2) is insufficient.
Combining statements. If pick values P=6, Q=2, R=3 6/2*3=1 integer but for values P=12, Q=4, R=6, 12/4*6=1/2 non-integer. So both statements together are insufficient. the answer is E.
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