A and B together to fill the whole tank in 20/3 min. The efficiency ratio of A and B is 5: 4. B and C together can fill the same tank in 60/7 min. If A and C together opened for 6 minutes and the remaining x% of the tank is to be filled by C. Find the value of x.
1
30%
2
15%
3
20%
4
25%
5
10%