Question

A proof-reader can read 40 pages in one hour. How many pages can this proof-reader read in 90 minutes?

Answer 1

Hint: This question is from algebra. In this question, we will first convert the one hour in minutes. After that, we will find out how many pages can be read in one minute. After that, we will find out how many can be read in 90 minutes. After solving the further question we will get our answer.

Complete step-by-step solution:
Let us solve this question.
In this question, we have given that a proof-reader can read 40 pages in one hour. So, we have to find out how many pages he can read in 90 minutes.
So, we can say from the question that
Proof-readers can read 40 pages in one hour.
We know that in 1 hour, there is 60 minutes.
So, we can say that a proof- reader can read 40 pages in 60 minutes.
We can write this as
In 60 minutes, he reads 40 pages. Then,
In 1 minute, he reads \[\dfrac{40}{60}\] pages. Now, for 90 minutes we can write
In 90 minutes, he reads \[\dfrac{40}{60}\times 90\] pages.
Now, let us solve for \[\dfrac{40}{60}\times 90\]. As we know that 40 can be written as 2 multiplied by 20, 60 can be written as 3 multiplied with 20, and 90 can be written as 3 multiplied with 30. So, this can be written as
\[\dfrac{40}{60}\times 90=\dfrac{20\times 2}{20\times 3}\times 30\times 3=\dfrac{2}{3}\times 30\times 3=2\times 30=60\]
So, we can say that
In 90 minutes, he reads 60 pages.
Hence, we have found our answer.
So, we can say that the proof-reader can read 60 pages in 90 minutes.

Note: As we can see that this question is from the topic of algebra, so we should have a better knowledge in that topic. We should know how to solve this type of question. We should know that 1 hour has 60 minutes. We should know the multiplication of some specific terms that is \[20\times 2\] can also be written as 40, \[20\times 3\] can also be written as 60, and \[30\times 3\] can also be written as 90.