There are m boys and 12 girls in a class. What is the probability of selecting at random a girl from the class?
Simplify \(7\frac{1}{2}-\left(2\frac{1}{2}+3\right)\div16\frac{1}{2}\)and correct your answer to the nearest whole number
Find the area of a rectangle of length 4cm and whose diagonal is 8cm, (Leave your answer in surd form)