<PRE><B>Question 385312</B>
You have two variables, so you need to make two equations.


Let x = number of books bought online
Let y = number of books bought in store


There were 250 books sold in total:


x+y = 250


Their sales totaled $4995:


15x + 22.50y = 4995


Use elimination or substitution with the two equations to solve for x and y. I will use elimination, by multiplying the first equation by 15, then subtracting.


15x + 22.50y = 4995
15x + 15y = 3750
-----------------
0 + 7.50y = 1245


y = 1245/7.50
y= 166


Now find x:

x+y=250
x+166=250
x=250-166
x=84


So there were 84 books sold online, and 166 sold in the store. Hope this helps! Let me know if you need any more help.
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