A total of 135 gold files and silver files are in a container. The ratio of gold files to silver files was 1 : 4. Some green files and brown files were put into the container. For every 9 silver files that were already in the container, 13 brown ones were added. Then, the final number of gold files and green files was ¹₈ the final number of silver files and brown files. Find the total number of green and brown files.

Green files	Gold files	Silver files	Brown files
	1x9	4x9
		9x4	13x4
1x11		8x11
2 u	9 u	36 u	52 u

The number of silver files is repeated.  Make the number of silver files the same.  LCM of 4 and 9 is 36.

The total number of silver files and brown files is repeated.  Make the total number of silver and brown files the same.  LCM of 88 and 8 is 88.

Total number of gold files and silver files
= 9 u + 36 u
= 45 u

45 u = 135

1 u = 135 ÷ 45 = 3

Total number of green and brown files
= 2 u + 52 u
= 54 u
= 54 x 3
= 162

Answer(s): 162