Question

Marcos buys 20 folders and 10 binders for a total of $100. Alicia buys 10 folders and 20 binders for $110. What is the price of each folder and each binder?​

Answer 1

folder is $3 binder is $4

Explanation:

Let folder be x and binders be y

Marcos

20x+10y= 100----------1

Alicia

10x+20y= 110-------------2

solve 1 and 2

20x+10y= 100 X 1

10x+20y= 110 X 2

20x+10y= 100

-20x+40y= 220

-30y= -120

y= 120/30

y= 4

put y= 4 in 1

20x+10y= 100

20x+10(4)= 100

20x+40=100

20x=100-40

20x=60

x= 60/20

x=3