Yan has already finished 27 of the 45 math problems he was assigned today. Each math problem took him 1Four-fifths of a minute to complete. If this pace continues, how much more time, to the nearest minute, will the rest of the problems take him to finish?

18 minutes
27 minutes
32 minutes
43 minutes

1 answer

First, we need to determine how many problems Yan has left to complete. Since he has finished 27 out of 45 problems, he has:

\[ 45 - 27 = 18 \text{ problems left} \]

Next, we know that each problem takes him \( \frac{4}{5} \) of a minute to complete. To find out how much time it will take him to complete the remaining 18 problems, we calculate the total time for the remaining problems:

\[ \text{Time for remaining problems} = \text{Number of problems} \times \text{Time per problem} \]

Substituting in the values:

\[ \text{Time for remaining problems} = 18 \times \frac{4}{5} \]

To carry out the multiplication:

\[ 18 \times \frac{4}{5} = \frac{18 \times 4}{5} = \frac{72}{5} = 14.4 \text{ minutes} \]

Now we round 14.4 minutes to the nearest minute, which gives us:

\[ 14.4 \approx 14 \text{ minutes} \]

Since the question asks how much more time to the nearest minute the rest of the problems will take to finish, we conclude that the nearest minute is:

\[ 14 \text{ minutes} \]

However, this option does not appear listed in your choices (18 minutes, 27 minutes, 32 minutes, 43 minutes). Thus, none of the provided answers match the calculated time. Please double-check the options or any assumptions.