Oliver, Rael, Sam and Vincent went shopping with a total of $561. After shopping, they had a total of $137 left. Rael spent $30. The amount Sam spent was ³₄ the amount spent by Oliver. The total amount spent by Oliver and Rael was $164 less than the total amount spent by Sam and Vincent. How much did Oliver and Vincent spend altogether?

	Oliver	Rael	Sam	Vincent	Total
Before					$561
Change	- 4 u	- $30	- 3 u	- ?	- $424
After					$137

Total amount that Oliver, Rael, Sam and Vincent spent
= 561 - 137
= $424

Total amount that Oliver and Rael spent
= 4 u + 30

Total amount that Sam and Vincent spent
= 4 u + 30 + 164
= 4 u + 194 

Total amount that Oliver, Rael, Sam and Vincent spent
= 4 u + 30 + 4 u + 194
= 8 u + 224 

8 u + 224 = 424
8 u = 424 - 224
8 u = 200 

1 u = 200 ÷ 8 = 25

Total amount that Rael and Sam spent
= 3 u + 30
= 3 x 25 + 30
= 75 + 30
= $105

Total amount that Oliver and Vincent spent
= 424 - 105
= $319

Answer(s): $319