SOLUTION: In a science test a class of 30 students had an average of 80. The 20 girls had an average of 85. Whats the average of the 10 remaining boys?

Question 328054: In a science test a class of 30 students had an average of 80. The 20 girls had an average of 85. Whats the average of the 10 remaining boys?
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
In a science test a class of 30 students had an average of 80.
The 20 girls had an average of 85.
What's the average of the 10 remaining boys?
:
Let x = av of the 10 boys
:
= 80
multiply both sides by 30, results
20(85) + 10x = 30(80)
1700 + 10x = 2400
10x = 2400 - 1700
10x = 700
x =
x = 70 is the av of the 10 boys
RELATED QUESTIONS
In a science test, a class of 30 students had an average of 80. The 20 girls in the class (answered by Fombitz)

In a science test, a class of 30 students had an average of 80. The 20 girls in the class (answered by KMST)

A class of 20 students took a math test. The 12 girls in the class had an average score... (answered by stanbon)

two classes of high school students take the same test . once class of 20 students had an (answered by Fombitz)

On a certain test, a class with 10 students had an average score of 60 and a class with... (answered by checkley79)

What is the detail solution of this question: In a class of 50 students the boys... (answered by stanbon)

30 students had an average of X, while 20 students had an average of 80. What is the... (answered by fractalier)

In BUBT, business faculty’s students were randomly assigned to one of two Math teachers (answered by ikleyn)

A class of 25 students took a math test. Ten students had an average of 88. The other... (answered by TimothyLamb)