A student scored 83 and 91 on her first two quizzes. Write and solve a compound inequality to find the possible values for a third quiz score that would average between 85 and 90. Inclusive.
A. 85

Question

A student scored 83 and 91 on her first two quizzes. Write and solve a compound inequality to find the possible values for a third quiz score that would average between 85 and 90. Inclusive.
A. 85 <= 83 + 91 + n (over) 3<= 90;81<=n<=96
B. 85 <= 83 + 91 (over) 2 <= n; -2 <= n <= 3
C. 90 <= 83 + 91 + n (over) 3 <=85;96<=n<=81
D. 83 <= 83 + 91 + n (over) 3 <=90;73<=n<=94

campbell_st · Answer

well the lower limit of the mean is 85 and upper mean  is 90

so 

$$85 \le \frac{83 + 91 + n}{3} \le 90$$

so just solve for n...

anonymous · Answer

i think it is A because it cant be less than the average cant be less than 85 but it can be greater than 90 so D is automatically out because it wants the average at an 83 and B is also out because it says that the average is between 85 and 3 so that narrows it down to 2 answer choices.. hope i helped. (:

anonymous · Answer

Thank you both :)

anonymous · Answer

Np :P