A manager purchased a total of 25 short sleeved and long sleeved shirts. Each short sleeved shirt costs $15 and each long sleeved shirt costs $20. If the manager spent a total of $425, how many short sleeved shirts did the manager buy?

ANSWER: 15 short sleeved shirts

Steps:

Use system of equations where x is short sleeved and y is long sleeved.

x+y=25
15x+20y=425

Make the coefficient of x the same in both equations.

Solve by elimination

15x+15y=375
-15x+20y=425
=-5y=-50

Divide both sides by -5 to isolate x
= y=10
This is the number of long sleeved shirts the manager bought.

Substitute y into the second equation to find the number of short sleeved shorts the manager bought.

15x+20(10)=425
= 15x+200=425
= 15x=225
= x=15

So the final answer is that the manager bought a total of 15 short sleeved shirts and 10 long sleeved shirts.

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