Answer:
one equation would be S+ L=36for the number of shirts sold.
<h3>What is Cost Price?</h3>
This refers to the price which a seller or a merchant purchased a good and this would be a good determinant to find out the selling price so that he could make a good profit.
<h3>Selling Price</h3>
This refers to the price which a good is sold and there are several factors which are taken into account such as:
Mathematically, the<em> profit= </em>Cost price - Selling Price (Expenditure)
Please note that your question is incomplete so I gave you a general overview so that you could have a better understanding of the concept.
Read more about cost price here:
brainly.com/question/19104371
If Mary spent half of her allowance the equation will begin with 1/2x or 0.5x where x is her allowance and 0.5 is half of her allowance spent. Mary also earned 7 dollars by washing the car so this will be added to her allowance spent.
The problem says that after Mary has spent half of her allowance at the movies she was left with 18 dollars so that means that the equation must be equal to 18.
The equation you want to set up is
0.5x+7=18
Where, 18-7=11
0.5x=11
11/.5 = x
x = $22
Thus, Mary has a weekly allowance of 22 dollars.
