Question

There are some hats in a box. 1/6 of them are red, 1/3 of blue, and 3/7 of the remainder are green. If there are 27 green hats, how many hats are there altogether

Answer 1

Rhere are 30 hats all together

Answer 2

1/6 are red and 1/3 are blue 
that means 1/6 + 2/6 = 3/6 = 1/2 are either red are blue 
3/7 of the remainder is 3/14 of the total 
3/14 x = 27 
x = 27(14/3) = 126 

there are 126 caps 
126 / 6 = 21 are red 
126 / 3 = 42 are blue 
there are 63 left, of which 3/7 are green 
3/7 (63) = 27 ==> 27 green caps 

total of 126 caps

Hope this helps :)