216k views
2 votes
Mary is preparing for hercollege entrance exams. In a practicetest, she answered 12 problems in30 minutes. At this rate, how manyquestions can she expect to answer in150 minutes?

1 Answer

6 votes

Answer:

60 questions

Step-by-step explanation:

If the rate of the number of problems per minute is constant, we can write the following equation:


\frac{12\text{ problems}}{30\text{ minutes}}=\frac{x}{150\text{ minutes}}

Where x is the number of questions that she can answer in 150 minutes.

So, solving for x, we get:


\begin{gathered} (12)/(30)=(x)/(150) \\ (12)/(30)*150=(x)/(150)*150 \\ 60=x \end{gathered}

Therefore, Mary can expect to answer 60 questions in 150 minutes.

User Derio
by
4.7k points