Answer:
35 two-points questions.
Step-by-step explanation:
The exam is worth 145 points.
The exam has 50 questions.
Some questions are worth 2 points and;
Some are worth 5 points.
Let the number of two-points questions be x and;
The number of five-points questions be y
This creates a simultaneous equation below:
x + y = 50 ... (i)
2x + 5y = 145 ... (ii)
Multiplying (i) by 2 and (ii) by 1 we get;
2x + 2y = 100 ... (i)
2x + 5y = 145 ... (ii)
Subtracting (ii) - (i) we get;
0 + 3y = 45
3y = 45
y = 15
So the number of five-points questions is 15 and the number of two-points questions is 50 - 15 = 35
