Ethan had to paint some containers. On the first day, the number of containers he painted was 20% of the number of containers that he had not painted. One week later, he painted another 109 containers. As a result, the total number of painted containers became 18 more than ²₅ of the total number of containers. How many more containers were unpainted than painted on the first day?

	Painted	Not painted	Total
Before	1x5 = 5 u	5x5 = 25 u	6x5 = 30 u
Change	+ 109	- 109
After	5 u + 109	25 u - 109	30 u
Comparing painted and not painted containers in the end	2x6 + 18 = 12 u + 18	3x6 - 18 = 18 u - 18	5x6 = 30 u

20% = ²⁰₁₀₀ = ¹₅
Painted : Not painted = 1 : 5

The total number of containers remains unchanged. Make the total number of containers at first and in the end the same.  LCM of 6 and 5 is 30.

The number of containers painted in the end is repeated.

12 u + 18 = 5 u + 109
12 u - 5 u = 109 - 18
7 u = 91

1 u = 91 ÷ 7 = 13

Number of more containers that were not painted than painted on the first day
= 25 u - 5 u
= 20 u
= 20 x 13
= 260

Answer(s): 260