What is the probability of drawing a red marble?

Answer:
[tex] \sf \: \frac{1}{4} [/tex]
Step-by-step explanation:
since the total of red marbles is 5 and the total of all the colours of marble is 20
therefore we write it like this;
[tex] \sf \frac{Total \: of \: red \: marbles}{Total \: of \: all \: the \: marbles}[/tex]
[tex] \rightarrow \sf \: \frac{5}{20} = \frac{1}{4}[/tex]