In a survey, the favourite ice-cream flavours chosen by 20 students are listed below:
Vanilla, Chocolate, Strawberry, Vanilla, Chocolate, Vanilla, Mango, Chocolate, Strawberry, Vanilla, Mango, Chocolate, Vanilla, Chocolate, Strawberry, Vanilla, Chocolate, Vanilla, Mango, Chocolate
What is the relative frequency (as a percentage) of Chocolate?
(a) 54\%
(b) 35\%
(c) 30\%
(d) 40\%