Question

Rachael had an average score of 88 on 7 equally-weighted tests. Her teacher decided to drop the lowest test grade. Rachael's average forthe 6 remaining tests is now 91. What was Rachael's lowest test score before her teacher removed that score?

Answer 1

Let:

x = Rachael's lowest test score

y = average score of the other tests

Rachael had an average score of 88 on 7 equally-weighted tests. so:

`88=(x+y)/(7)`

Her teacher decided to drop the lowest test grade. Rachael's average for

the 6 remaining tests is now 91. so:

`\begin{gathered} 91=(y)/(6) \\ so\colon \\ y=6\cdot91 \\ y=546 \end{gathered}`

Replace the valuel of y into the first equation:

`88=(x+546)/(7)`

solve for x:

`\begin{gathered} 88\cdot7=x+546 \\ 616=x+546 \\ x=616-546 \\ x=70 \end{gathered}`