Tammy and Joelle have some biscuits each. If Tammy gives Joelle 4 biscuits, Tammy will have ³₄ as many biscuits as Joelle. If Tammy gives Joelle 2 biscuits, they will have an equal number of biscuits. How many biscuits does Tammy have at first?

	Case 1		Case 2
	Tammy	Joelle	Tammy	Joelle
Before	3 u + 4	4 u - 4	3.5 u + 2	3.5 u - 2
Change	- 4	+ 4	- 2	+ 2
After	3 u	4 u	3.5 u	3.5 u

Total number of biscuits that Tammy and Joelle have
= 3 u + 4 u
= 7 u 

Number of biscuits that Tammy and Joelle each has in the end is the same.

Number of biscuits that Tammy and Joelle each has in the end in Case 2
= 7 u ÷ 2
= 3.5 u

Number of biscuits that Tammy had at first is the same in Case 1 and Case 2.

3.5 u + 2 = 3 u + 4
3.5 u - 3 u = 4 - 2
0.5 u = 2

1 u = 2 ÷ 0.5 = 4

Number of biscuits that Tammy has
= 3 u + 4
= 3 x 4 + 4
= 12 + 4
= 16

Answer(s): 16