There are 30 pens in a box. 12 of the pens are black.
7 of the pens are green.
The rest of the pens are red.
One of the pens is chosen at random.
Find the probability that the pen is red.

Students are given 3 minutes for each multiple-choice question and 5 minutes for each free-response question on a test. there are 15 questions on the test, and students are given 51 minutes to take it. how many multiple-choice questions are on the test?

Two corresponding sides of two similar triangles are 3cm and 5cm. the area of the first triangle is 12cm^2. what is the area of the second triangle?

On a cm grid, point p has coordinates (3,-1) and point q has coordinates (-5,6) calculate the shortest distance between p and q give your answer to 1 decimal place