Q18,paper 2,D 12.Given the following expressions of a grammar

E  -> E * F / F + E / F

F -> F – F / id

Which of the following is true ?

(A) *has higher precedence than +

(B) – has higher precedence than *

(C) + and – have same precedence

(D) + has higher precedence than *

Answer(B).

Lowest precedence operators are last, at the top of tree.

Make the derivation tree and check that * is always on the top. That is why – has higher precedence than *.