Answer:
- 10 questions that are 4-point
- 30 questions that are 2-point
Step-by-step explanation:
<em>Numerical reasoning</em>
If all questions were 2-point, the total score would be 80. It is 20 more than that. Each 4-point question that replaces a 2-point question will add 2 points to the score, so there must be 20/2 = 10 of them.
There are 10 4-point questions and 30 2-point questions.
_____
<em>With an equation</em>
Let x represent the number of 4-point questions. Then 40-x is the number of 2-point questions. The total number of points is ...
... 2(40-x) +4x = 100
... 2x +80 = 100 . . . . simplify
... 2x = 20 . . . . . . . . .subtract 80
... x = 10 . . . . . . . . . . divide by 2.
There are 10 4-point questions and 40-10=30 2-point questions.