A Substance,A₂B,has the Composition by Mass of 60% a and 40

Multiple Choice

A substance,A₂B,has the composition by mass of 60% A and 40% B.What is the composition of AB₂ by mass?

A) 40% A,60% B
B) 50% A,50% B
C) 27% A,73% B
D) 33% A,67% B
E) none of these