We can solve this system using elimination:
(x+y=24)3
3x+5y=100
3x+3y=72
-(3x+5y=100)
0x-2y=-28
y=14
We can then plug this back into one of the original equations:
x+14=24
x=10
We can check our answer by plugging this into both of the original equations:
10+14=24
24=24
3(10) + 5(14)=100
30+70=100
100=100
Therefore, there are 10 3-point questions and 14 5-point questions.
Answer:
1. 12 boys,
5. 15 hours
6. 36
Im not so sure on the others, Gl!
