Quote:
If a certain school will buy computers at a fixed price of x dollars each and computer desks at a fixed price of y dollars each, how many dollars will the school pay for each computer?
(1) The school will pay a total of $2,200 if it buys 2 computers and 1 computer desk at these fixed prices.
(2) The school will pay a total of $5,400 if it buys 5 computers and 2 computer desks at these fixed prices.
A quick thing that can be helpful to know is if you have two unknown variables and two equations, you can figure out what each variable is. One thing, however, to be careful of is if the two equations are twins. If, for example, you are told a + b = 10 and 2a + 2b = 20, it's not possible to figure out what "a" or "b" is since the equations aren't meaningfully different.
In this question, we don't need to worry about that. The two equations are meaningfully different. You could at this point decide to quickly choose (C) since you require both statements, but if you want to be a little careful before doing so, you could solve for x, the price paid for each computer.
Statement 1 tells us 2x + y = 2200
Statement 2 tells us 5x + 2y = 5400
2x + y = 2200 means 4x + 2y = 4400
5x + 2y = 5400 minus 4x + 2y = 4400 would leave x = 1000
(C) is your answer.