A test has twenty questions worth 100 points the test consists of true or false worth 3 points each and multiple choice ouestions worth 11 points each how many multiple choice questions are there in test
Answers
Answer:
5 multiple choice questions and 15 true or false questions
Let ' a ' be the number of True/False questions and ' b ' be the the number MCQ questions.
Total questions = 30.
It means,
a + b = 20 _____________ ( ! )
It is also given that the true/false questions are worth 3 points. So the number of points we could score on these questions :
- 3 × a
The Multiple Choice questions are worth 11 points each. So the number of points we could score on these questions :
- 11 × b
Now,
if we add up the total number of points possible, the result will be
100 points.
That is,
3a + 11b = 100 ________ ( !! )
Now,
Observe ( ! ) and subtract a from both sides. After the subtraction ,
b will be canceled from the left side and the equation formed will be :
⇒ a = 20 - b
Now,
substitute the value of ' a ' in question ( !! ).
We get,
3(20 - b) + 11b = 100
⇒ 60 - 3b + 11 b = 100
⇒ 60 + 8b = 100
⇒ 8b = 100 - 60
⇒ 8b = 40
⇒ b = 40/8
∴ b = 5
Hence,
There were total 5 MCQ questions in the test.