Posted by **Kahlil** on Wednesday, November 9, 2011 at 6:14pm.

Ms Newton's class took the same test as Mr. Euclid's students. Ms. Newton's class has 20 students, and the average(mean) test score was 90. The average of Mr. Euclids class was 80. If you combine both classes the average score on the test is 85. How many students does Mr. Euclid have in his Mathematics class?

- Algebra -
**Steve**, Wednesday, November 9, 2011 at 8:39pm
If Newton had 20 students and Euclid had e students,

total points = 20*90 + e*80

total students = 20+e

total average = (20*90 + e*80)/(20+e) = 85

1800 + 80e = 1700 + 85e

100 = 5e

e = 20

Makes sense. 85 is halfway between 80 and 90, so there must have bee the same number of students in each class.

- Algebra -
**Daniel**, Thursday, November 8, 2012 at 6:46pm
Luisa mows lawns during the summer. She charges $15 if she cuts the grass but charges $5 more if she also trims the grass. Last week she trimmed 5 more yards than she cut. If she made $415 last week, how many yards did she trim?

## Answer This Question

## Related Questions

- Algebra - Ms Newton's class took the same test as Mr. Euclid's students. Ms. ...
- math hw - 10.Thirty students in a chemistry class took a test on which the ...
- Help math!! - 15 students took a science test. the average score was 88.0. later...
- math - 15 students took a science test. the average score was 88.0. later in the...
- Algebra - The 22 students present for a recent test in Ms. Huangâ€™s class had an ...
- algebra 2 - The average (arithmetic mean) of the test scores of class of a class...
- Math - The score for half of the students in a class on a certain test was 90. ...
- math - In his NPR radio program "A Prairie Home Companion," Garrison Keillor ...
- Algebra - On a math test, k students in the class averaged 80%. The remaining ...
- Statistics - A student wants to test her hypothesis she gives each of her ...

More Related Questions