Answer:
Mandy sold 250 pancakes and 50 waffles.
Step-by-step explanation:
From the information given, you can say that the sum of pancakes and waffles is equal to 300:
x+y=300
Also, the statement indicates that she charges $3 per pancake, $1 per waffle, and made a total of $800 and you can express this as:
3x+y=800
You have the following equations:
x+y=300 (1)
3x+y=800 (2), where:
x is the number of pancakes she sold
y is the number of waffles she sold
Now, you can solve for x in (1):
x=300-y (3)
Then, you can replace (3) in (2):
3(300-y)+y=800
900-3y+y=800
900-800=2y
100=2y
y=100/2
y=50
Finally, you can replace the value of y in (3) to find x:
x=300-50
x=250
According to this, the answer is that Mandy sold 250 pancakes and 50 waffles.