Question

Alex answered $35$ out of $50$ questions correctly in a math quiz. If he has answered $70$ questions correctly in the chemistry quiz, with the same accuracy as that of the math quiz, find the total number of questions in the chemistry quiz.

• A. $99$
• B. $50$
• C. $52$
• D. $100$

Answer 1

The correct option is D $100$

Number of questions solved correctly in the math quiz = $35$
Total number of questions in the math quiz = $50$

Ratio of the number of questions solved correctly to the total number of questions in the math quiz = $35:50$

Let the number of questions in the chemistry quiz be $x$.

As the accuracy remains the same in the math and chemistry quizzes, the ratio of the number of questions answered correctly to the total number of questions will also remain the same.

$\Rightarrow 35:50::70:x$

$\Rightarrow \frac{35}{50}=\frac{70}{x}$

By cross-multiplication, we get:


$35\times x=70\times 50$

$\Rightarrow x=\frac{70\times 50}{35}$

$\Rightarrow x=100$

Therefore, the chemistry quiz had a total of $100$ questions.