The table below shows the distribution of students by age in a high school with 1500 students. What is the probability that a randomly chosen student is
14 years old?

Age
13, 14, 15, 16, 17, 18
Number of Students
15,375,450,420,225,15

A. 0.15
B. 0.30
C. 0.28
D. 0.25

Are you asking for 6 or 15?

So the first thing we do is to multiply the top equation by 3. the reason i want to do this is i notice there will be a 6y on both equations and can possibly add/subtract them. so we get 6y = -3x + 27. adding that and the second equation we get 6x = 27-15 which is 12. divide by 6 and we get 2. ∴ x = 2. substituting 2 into the first equation we get 2y = -2 + 9 which is 7. divide by 2 and we get 7/2. ∴ y = 7/2, x = 2.