4. Maximum 15 points. The company "Superheroes, Inc" urgently called Superman and Flash to perform some construction work to build protective structures against a hurricane. It is known that Flash's productivity is twice that of Superman. The payment for each superhero depends only on the time they spend on the work, as follows: $w=90 / t$, where $w$ is the amount of money the superhero will receive, and $t$ is the time in minutes they spend on the work. Flash was 1 minute late to the start of the construction, and during this time, Superman managed to complete $10 \%$ of the total work. The rest of the construction was completed together by both superheroes. How much money did each superhero receive for the work they completed?
# Solution:

9/10 of the work was completed together by the superheroes, with 3/10 done by Superman and 6/10 by Flash, since his productivity is twice as high. Since 1/10 of the entire work was completed by Superman in 1 minute, 3/10 of the work will take him 3 minutes. At the same time, Flash will also work for 3 minutes, as they will finish the work simultaneously. Then Superman will receive $90 / (1+3) = 22.5$, and Flash will receive $90 / 3 = 30$.

## Grading Scheme:

Fully correct solution - 15 points.

Correctly found the working time of each superhero, but did not find the amount of money - 10 points out of 15.

Incorrectly found the working time of each superhero, but the logic of the search is correct - 5 points out of 15.