Question 53324
I hope this isn't a real life example!
Let the final equal: x
The grade is found by 2/3*midterm+1/3*final.
She got a 48 on the midterm.
She wants a score between 70 and 79.
{{{70<(2/3)*48+(1/3)*x<79}}}
{{{70<96/3+x/3<79}}}
{{{70<32+x/3<79}}}
{{{-32+70<-32+32+x/3<-32+79}}}
{{{38<x/3<47}}}
{{{3*38<(3*x)/3<3*47}}}
{{{114<x<141}}}
Ask yourself if this seems reasonable.  2/3's of her grade was a 48.  It does seam unlikely that she can bring her grade up at least 22 points with only 1/3 of a grade left.
Wendy is going to need a lot of bonus points!