In two types of stainless steel, the ratio between chromium and stee are 2:11 and 5:21 respectively. If these two types of stainless steel are mixed together to form a new stainless steel in which the ratio of chromium to steel is 7:32, then find the ratio in which these two types of stainless steel are to be mixed together.
1
3 : 4
2
1 : 2
3
2 : 3
4
2 : 1