1 All Year 9 students in a school must choose either Music or Drama but not both. In 2013 the numbers taking the options of Music or Drama were in the ratio, 3:7.
The number of students choosing Music was 72.
a) What percentage of these students chose Music?
b) How many students were there in total in Year 9?

Which expression can be used to determine the slope of the line that passes through the points -6, three and one, -9

An optical inspection system is used to distinguish among different part types. the probability of a correct classification of any part is 0.92. suppose that three parts are inspected and that the classifications are independent. let the random variable x denote the number of parts that are correctly classified. determine the probability mass function of x. round your answers to four decimal places (e.g. 98.7654). x f(x) 0 1 2 3

What are the solutions of the system? solve by graphing. y = -x^2 -6x - 7 y = 2