A group of students were given a spelling test. The table shows their marks.
Mark
Frequency
6
5
a) Work out the range of the marks.
7
4
8
7
b) How many students are in the group?
9
10
10
4
c) Work out the mean mark of the group.

Afactory adds 3 red drops and 2 blue drops of coloring to white paint to make each pint of purple paint. the factory will make 50 gallons of the purple paint.how many drops of red and blue coloring will the factory need in the 50 gallon batch of purple paint.

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

The base of a triangle exceeds the height by 9 inches. if the area is 180 square inches, find the length of the base and the height of the triangle.