Seven friends P, Q, R, S, T, U and V, each has a different age. P is older than only U and R. R is older than U. Q is older than S but younger than T. T is not the oldest among all. The age of how many persons is between the ages of Q and R?

2

The logic followed here is:

Step 1: P is older than only U and R.

Step 2: R is older than U.

So, P>R>U

Step 3: Q is older than S but younger than T.

So, T> Q>S

Now on combining all the above steps we get:

T> Q> S> P> R> U

Step 4: T is not the oldest among all.

V> T> Q> S> P> R> U

Therefore, The age of two persons is between the ages of Q and R.