First, let's calculate the distance Will travels before grace even leaves.
Since he traveled for 45 minutes, we have
(45min)(50m/min)=2250m
So when Grace starts, she and Will have
(2800m)–(2250m)=550m to cover.
Let's let t be the amount of time it takes for the two to catch up to each other after Grace starts rowing.
We have the equation
(50)(t)+(30)(t)=55080t=550t=550/80=6.875
This is approximately 6 minutes and 52 seconds.
So the clock time they meet is 6 min 52 sec after Grace starts.
Grace started at 2:45, so add 6 min 52 sec and the clock will read 2:51:52 pm when they meet
Thus, our final answer is 2:51:52
Thanks! :)