The total sales consisted of two types of T shirts, the standard model that sells for $12.50 a T shirt and the upgraded silk screened T shirt that sells for $15 a T shirt.

Question

At the end of first month total sales for the T shirts were $22,525. 

The total sales consisted of two types of T shirts, the standard model that sells for $12.50 a T shirt and the upgraded silk screened T shirt that sells for $15 a T shirt. 

They sold a total of 1,642 T shirts for the month. 

a) How many T shirts did they sell of the standard model?

b) How many upgraded silk screened T shirts did they sell?

Answer 1

Set up two equations:

one for total sales: 12.50t + 15s = 22,525

one for total shirts sold: t + s = 1,642

Then, choose one variable in value of the other, That is: s = 1,642 - t

Substitute this value for s in the initial equation: 12.50t + 15(1,642 - t) = 22,525

Distribute the 15 over the quantity (1642 - t): 12.50t + 24,630 - 15t = 22, 525

Combine like terms: -15t + 12.50t = 22,525 - 24,630

step 2: -2.50t = -2,105

Divide both sides by -2.5t/2.5 = -2,105/-2.5

t = 842 842 T-shirts were sold of the standard model.

Substituting the value of t in the second equation:

Thus, s = 1,642 - 842 = 800 800 upgraded silk-screened T-shirts were sold.