Let x represent the number of vehicles that the sales person sold in a month.
The sales person at the car dealership earns a monthly salary of $2400 and $250 for each vehicle sold. Let y represent the total amount he earns for selling x vehicles in a month. Therefore,
y = 250x + 2400
To determine the number of vehicles that the sales person needs to sell in a month to earn exactly $4000, we would substitute
4000 for y. It becomes
4000 = 250x + 2400
250x = 4000 - 2400 = 1600
x = 1600/250
x = 6.4
He would have to sell 7 vehicles because he cannot sell 6.4 vehicles and if he sells 6 vehicles, it would be lesser than $4000
