So the cost for renting the car for one day and driving it for 400 miles would be around 15 + 400 (0.4) = 160 + 15 = 175$
To write an expression for a day you can obviously just make up one by putting in x as the number of miles. So to calculate the cost for x miles you can write x * (0.4) and more over at the end we have to add the 15$ so the expression equals to 15 + 0.4 (x)
First off change everything to minutes. The 600 is irrelevant in this problem. He can mow this size in 80 minutes. 8 hours is 8x60= 480. 480/80 is 6 and therefore he can mow 6 lawns in this size in time of 8 hours
