P, Q, R and S are four friends. P is shorter than Q but taller than R who is shorter than S. Who is the shortest among all?

Step 1: From the first part, we know:

P < Q (P is shorter than Q)

P > R (P is taller than R)

Step 2: From the second part:

R < S (R is shorter than S)

Now order them:

Since P is taller than R and R is shorter than S:

• Q is the tallest (P is shorter than Q)
• Then P
• Then S (since R < S but P > R, S must be between P and R)
• Then R

Final Order (Tallest to Shortest): Q > P > S > R

Answer: R is the shortest among all.