1990 AMC 12 #24
Source:
December 31, 2011
ratioAMC
Problem Statement
All students at Adams High School and at Baker High School take a certain exam. The average scores for boys, for girls, and for boys and girls combined, at Adams HS and Baker HS are shown in the table, as is the average for boys at the two schools combined. What is the average score for the girls at the two schools combined?
\begin{tabular}{c c c c}
{} & Adams & Baker & Adams and Baker \\
Boys: & 71 & 81 & 79 \\
Girls: & 76 & 90 & ? \\
Boys and Girls: & 74 & 84 & \\
\end{tabular}
(A)\ 81 \qquad(B)\ 82 \qquad(C)\ 83 \qquad(D)\ 84 (E)\ 85