If P,Q,R are physical quantities, having different dimensions, which of the following combinations can never be a meaningful quantity (a) (P-Q)/R (b) PQ-R (c) PQ/R (d) (R+Q)/P

Dear student
According to dimensional analysis P,Q,R are physical quantities two different physical quantities can never be subtracted or added   but can be multiplied or divided like option b, c 


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