A shopper keeper sold a total of 15 boxes of pencils on Monday and Tuesday. She still three more boxes on Monday then on Tuesday. There were 12 pencils in each box. How many pencils did she sell on Monday?
counting boxes, with x sold on Monday,
x + x-3 = 15
12x is the number of pencils.
To find out how many pencils the shopper sold on Monday, we need to use the given information.
Let's assume the number of boxes sold on Monday is x.
According to the information, the shopper sold three more boxes on Monday than on Tuesday. This means that the number of boxes sold on Tuesday is x - 3.
We know that the total number of boxes sold on Monday and Tuesday is 15. So, we can set up an equation:
x + (x - 3) = 15
Now we can simplify and solve the equation for x:
2x - 3 = 15
2x = 18
x = 9
Therefore, the shopper sold 9 boxes of pencils on Monday.
Since each box contains 12 pencils, the total number of pencils sold on Monday is:
9 boxes * 12 pencils/box = 108 pencils
So, the shopper sold 108 pencils on Monday.