The test question shall contain 20 questions in all.
Therefore, if the 2-point question is x, and the 4-point question is y then
x + y = 20
Also, all the 2-point questions plus all the 4-point questions all added together would equal 50points. Therefore, that would be
2x + 4y = 50
With these pair of simultaneous equations we can now solve as follows;
[tex]\begin{gathered} x+y=20---(1) \\ 2x+4y=50---(2) \\ \text{Make x=20-y in equation (1)} \\ \text{Substitute for the value of x into equation (2)} \\ 2(20-y)+4y=50 \\ 40-2y+4y=50 \\ \text{Collect all like terms} \\ 4y-2y=50-40 \\ 2y=10 \\ \text{Divide both sides by 2} \\ y=5 \\ \text{Substitute for the value of y into equation (1)} \\ x+y=20 \\ x+5=20 \\ \text{Subtract 5 from both sides} \\ x=15 \end{gathered}[/tex]Therefore, Janice can include
15 two-point test
