What are the numbers usually denoted by Q and R ?

If the natural numbers, the integers , the rational numbers and the real numbers are denoted by N,Z,Q and R respectively , then which one of the followings is correct ?

A fair dice is thrown three times. If p, q and r are the numbers obtained on the dice, then find the probability that i^(p) + i^(q) + i^(r) = 1 , where I = sqrt(-1) .

A cubic solid is made of two elements P and Q. Atoms of Q are at the corners of the cube and P at the body centre. What is the formula of the compound? What are the coordination number of P and Q?

What is the usual number of valence electrons in the atoms of the last element in a period?

Two radioactive nuclei P and Q in a given sample decay into a stable nucleus R. At time t=0, number of P species are 4N_0 and that of Q are N_0 . Half-life of P (for conversion to R) is 1 min whereas that of Q is 2min. Initially there are no nuclei of R present in the sample. When number of nuclei of P and Q are equal, the number of nuclei of R present in the sample would be

If the pth , qth and rth terms of an A.P. be P, Q and R respectively then show that, p(Q-R) + q(R-P) + r(P-Q) = 0 .

lf r, s, t are prime numbers and p, q are the positive integers such that their LCM of p,q is r^2 t^4 s^2, then the numbers of ordered pair of (p, q) is (A) 252 (B) 254 (C) 225 (D) 224

If R is the set of all real numbers, what do the cartesian products R xx R and R xx R xx R represent?

If r,s,t are prime numbers and p,q are the positive integers such that LCM of p,q is r^2t^4s^2 , then find the number of ordered pair (p,q).

Let , a , b ,c ,d , p ,q ,r be positive real number such that a ,b , c are in G.P and a^(p)=b^(q)=c^(r) Then-