Vincent had to paint some boxes. On the first day, the number of boxes he painted was 25% of the number of boxes that he had not painted. One week later, he painted another 215 boxes. As a result, the total number of painted boxes became 17 more than ³₄ of the total number of boxes. How many less boxes were painted than unpainted on the first day?

	Painted	Not painted	Total
Before	1x4 = 4 u	4x4 = 16 u	5x4 = 20 u
Change	+ 215	- 215
After	4 u + 215	16 u - 215	20 u
Comparing painted and not painted boxes in the end	3x5 + 17 = 15 u + 17	1x5 - 17 = 5 u - 17	4x5 = 20 u

25% = ²⁵₁₀₀ = ¹₄
Painted : Not painted = 1 : 4

The total number of boxes remains unchanged. Make the total number of boxes at first and in the end the same.  LCM of 5 and 4 is 20.

The number of boxes painted in the end is repeated.

15 u + 17 = 4 u + 215
15 u - 4 u = 215 - 17
11 u = 198

1 u = 198 ÷ 11 = 18

Number of less boxes that were painted than not painted on the first day
= 16 u - 4 u
= 12 u
= 12 x 18
= 216

Answer(s): 216