6m in length means that it is 10 tiles long because 60cm*10 = 6m
so 10 long
1.8m in height is the same as 6 tiles high since 30cm x 6 = 1.80m
so their is a total of 60 tiles.
3/5 will be white so thats 36 white ones
we have 24 tiles left and since its 1 green tile to every 3 blue if we times both by 6 we get 6 green tiles and 18 blue ones.
therefore frank will need
36 white
6 green
18 blue