Final answer:
It will take John 8 weeks to save enough money to buy the toy car.
Step-by-step explanation:
To determine the number of weeks it will take for John to save enough money to buy the car, we need to divide the cost of the car by the amount he saves each week. By dividing $15 by $2, we find that it will take him 7.5 weeks to save enough money. However, since we cannot have a fraction of a week, we round up to the nearest whole number. Therefore, it will take John 8 weeks to save enough money to buy the toy car.