Question

Kris spent $131 on shirts. Blue shirts cost $28, and red shirts cost $15. If he bought a total of 7 shirts, how many of each kind did he buy?

a) 3 blue shirts and 4 red shirts
b) 4 blue shirts and 3 red shirts
c) 2 blue shirts and 5 red shirts
d) 5 blue shirts and 2 red shirts

Answer 1

Kris bought 2 blue shirts and 5 red shirts after setting up a system of equations based on the total number of shirts and the total amount spent, and then solving for the number of each type of shirt.

Step-by-step explanation:

The question requires setting up a system of equations to solve for the number of blue and red shirts Kris bought. Let's denote the number of blue shirts as x and the number of red shirts as y. The total number of shirts is given as 7, which leads to our first equation: x + y = 7. Kris spent a total of $131, with blue shirts costing $28 each and red shirts costing $15 each, giving us a second equation based on the total cost: 28x + 15y = 131.

To solve the system of equations, we can use either substitution or elimination. We can start by solving the first equation for x: x = 7 - y. Then we substitute x in the second equation and get 28(7 - y) + 15y = 131. This simplifies to 196 - 28y + 15y = 131. Combining like terms, we get -13y = -65, leading to y = 5. Now we substitute y back into the equation x = 7 - y to find x, which will give us x = 2.

Therefore, Kris bought 2 blue shirts and 5 red shirts, which corresponds to option (c).