A garden company has increased the manpower for landscaping. Now, on average, 50 more trees are planted every day than originally planned, and the time required to plant 600 trees is the same as originally planned.
Suppose the original plan was to plant X trees a day on average, and now we plant (x+50) trees a day.
According to the meaning, 600 x+50 = 450 x
So choose: C.