If we translate the facts into location equations, xM=Mona's location, xL=Lina's location, then we get:
xM(t) = 300t
xL(t) = v*t - 1000
xM(10)=xL(10)
Where v is Lina's speed we have to find.
Plugging them all together gives:
300*10 = 10v - 1000
Which can be solved:
3000 + 1000 = 10v
4000 = 10v
v=400
Lina should skate at 400 feet per minute!
