This question is a bit confusing to me, but I think I grasped the concept. 1. x best represents Sarah's mom's age. 2. x - 24 best represents Sarah's mom's age minus how much younger Sarah is than her mom. 3. The expression would look a little like this: 2x-24 = 68 + 24 +24 2x = 92 /2 /2 x = 46.
Which means, Sarah is 22 and her mom is 46 years of age. If you need more clarification, I'd be more than happy to elaborate further.
Leasing a car is the better option if they only want to keep it for a certain amount of years. This is because with leasing you are only paying the depreciation of the car instead of the buying price. Also, it benefits people that can't pay the down payment for the car.