Mary makes two sizes of mugs: a small mug that she sells for 2 dollars and 50 cents and a large mug that she sells for 5 dollars and 75 cents. Yesterday Mary made 56 dollars. Before she opened her shop in the morning, she had 200 mugs in her inventory. At the end of the day she has 188. How many large mugs did she sell? How many small mugs did she sell?

Answer 1

Let
x = # large mugs sold
y = # small mugs sold
so, what have they told you?
Total income: 2.50x + 5.75y = 56.00
mugs sold = 200-188 = 12. So, x+y = 12

Now just solve for x and y

Answer 2

200 - 188 = 12 Mugs sold.

Sold X small mugs.
Sold 12-X Large mugs.

2.5x + 5.75(12-x) = 56.
5x/2 + 23/4(12-x) = 56,
10x + 23(12-x) = 224,
1ox + 276 - 23x = 224,
X = ?
12-X = ?.