Zeph had three boxes, containing a total of 1100 styrofoam bowls. The number of styrofoam bowls in Box L to the total number of styrofoam bowls was 3 : 10. He sold 432 styrofoam bowls from Box M and sold ¹₅ of the styrofoam bowls in Box N. The number of styrofoam bowls left in Box M to the number of styrofoam bowls left in Box N was 2 : 1. How many styrofoam bowls were there in Box M at first?

	Box L	Box M	Box N	Total
Before	3 u	7 u (770)		10 u (1100)
		8 p + 432	5 p
Change		- 432	- 1 p
			4 p
After		2x4 = 8 p	1x4 = 4 p

10 u = 1100
1 u = 1100 ÷ 10 = 110

Number of styrofoam bowls in Box M and Box N at first
= 7 u
= 7 x 110
= 770

The number of bowls left in N is the repeated identity.
LCM of 1 and 4 = 4

8 p + 432 + 5 p = 770
8 p + 5 p = 770 - 432
13 p = 338

1 p = 338 ÷ 13 = 26

Number of bowls in Box M at first
= 8 p + 432
= 8 x 26 + 432
= 208 + 432
= 640

Answer(s):640