Brad and Dana had the same grade on their last exam, and....

[iTRY]

Brad and Dana had the same grade on their last exam, and it was the highest grade for each of them that term. The grade raised Brad's average from an 83 to an 86. It raised Dana's average from 88 to 90. How many exams did they have before this last one?

how would i figure out the impact of one test grade on the average.. also, is it important to know the actual scores of the exams before solving? this seems like a very tricky problem.

 

[stapel]

Pick a variable for the number of exams before this one.

If Brad's average was 83 for however many exams he'd had, then what was his point total, in terms of your variable?

Pick a second variable for the score on this latest exam. Add this to his previous point total. This is his new point total.

Take your first variable, and add "1". This is the new total number of exams.

Use your new point total and your new total number of exams to find an expression for his new average. This expression will have two variables. Set this expression equal to his new average.

Do the same thing with Dana's information.

You now have two equations in two variables. Solve the system.

If you get stuck, please reply showing how far you have gotten. Thank you.

Eliz.