Question

In an objective type questions of 150 questions: John got 80% correct answers and Mohan got 64% correct answers. How many correct answers did each get?
A. John = 96
B. John = 120
C. Mohan = 120
D. Mohan = 96

Answer 1

Hint: Find 80% of 150 and then 64% of 150 for correct answers of John and Mohan respectively and then see which one matches from the options. There may be multiple correct answers so don't leave the question seeing that one of them matches.

Complete step-by-step answer:
It is already given that there are a total of 150 questions.
To find the number of questions done correctly by each of them, we just need to multiply the percent with the total number of questions one by one to get the correct answers.
Now we are also given that John got 80% correct answer so all we need to do is find 80% of 150.
\[\begin{array}{l}
\therefore 80\% of150\\
 = \dfrac{{80}}{{100}} \times 150\\
 = \dfrac{4}{5} \times 150\\
 = 4 \times 30\\
 = 120
\end{array}\]
Which means that option B is correct here
Let us check for mohan as he got 64% correct answers so all we need to do is find 64% of 150.
\[\begin{array}{l}
\therefore 64\% of150\\
 = \dfrac{{64}}{{100}} \times 150\\
 = \dfrac{{64}}{2} \times 3\\
 = 32 \times 3\\
 = 96
\end{array}\]
Which means option D is also correct.
So from here it is clear that B and D which is John = 120 and Mohan = 96 both are the correct options.


Note: A question may have multiple correct answers. A lot of students left the question just either by claiming B or D as the correct option and forget to check the others by completing the question. In such cases you can only get half of the marks the question has or sometimes no marks, depending upon the exam and the rules. Also note that while changing a percent to a regular number we have to divide it by 100. For example; \[45\% = \dfrac{{45}}{{100}}\]