Q:

In a different test, the mean score of 50 students is 54%The students are split in two groups. Group A and Group B.The mean score for Group A is 60% and the mean score for Group B is 50%How many students are in Group B and how many are in Group B?

Accepted Solution

A:
Answer:Group A has 20 studentsGroup B has 30 studentsStep-by-step explanation:The mean score of 50 students is 54%, so the sum of 50 scores, divided by 50 is 54%.  That means that 50(0.54) = 27 points were scored between the 50 students.Let x represent the number of students in Group ALet y represent the number of students in Group BWe have0.6x + 0.5y = 0.54(50)    (the points scored, times their averages is the total)andx + y = 50Use substitution to solve...solve the second equation for one variable...x = 50 - yNow plug that into the first equation...0.6(50 - y) + 0.5y = 27      30 - 0.6y + 0.5y = 27                      -0.1y = -3                    y =  30So there are 30 students in group B, therefore there are 20 students in group A