Question

Teri got a 44 and 72 on her 1st 2 algebra tests. In order to pass the class with a 60%, what is the lowest grade she can get on the remaining test????

Answer 1

Assuming that the entire class grade is just the average of the three tests (a poorly designed grading scheme if you ask me!) then you have to solve the following:

\[\frac{44+72+x}{300}=\frac{60}{100}\]

This is not so bad because you can add 44 and 72 because they are in the numerator of the left fraction...

\[\frac{116+x}{300}=\frac{60}{100}\]

Now reduce that 60/100 on the right hand side:

Divide by 10
\[\frac{116+x}{300}=\frac{6}{10}\]

Divide by 2
\[\frac{116+x}{300}=\frac{3}{5}\]

Ok, so from here we do some cross multiplication to solve for x. :)

Hope this helps!