The way I would look at it is that Sophia types 15 words per minute faster than Patty so every minute Sophia is 15 minutes closer to what Patty has done. 510/15=34 so after 34 minutes Sophia will have caught up to Patty
-6+3=-3
-6-3=-9
so -3 and -9
6 1/3 + k + 3 5/6 + 5 1/2 = 26 1/6
Add your fractions
6 1/3 + 3 5/6 + 5 1/2 = 15 2/3
now You need to isolate k on one side of the equation by using the subtraction method of equality.
k + 15 2/3 = 26 1/6
k = 10 1/2
Hope this helps
I had to edit
When multiplying fractions you multiply the denominators by the denominators and the numerators by the numerators
For example
4/5x 2/3
8/15
If you put it into your calculator by pressing the COS button and then typing in 105, you get -0.258819045...
