First Statement
James is older than Benito.
→Age of James > Age of Benito--------(1)
Second Statement
Benito is younger than Mariana.
→Age of Mariana > Age of Benito----------(2)
Third Statement
Mariana is younger than James.
→Age of James > Age of Mariana-----------(3)
Equating (1),(2) and (3)
→Age of James(J) > Age of Mariana(M)>Age of Benito(B)
⇒James will be farthest from right side of number line, that is Farthest distance from point 0(Zero), then Second Farthest from point 0" is Mariana, and then Third one will be Benito, nearest from point "0".