Solve for the value of n.

1. n : 15 = 30 : 10 n = ___
2. 5 : n = 160 : 320 n = ___
3. 3 : 5 = 75 : n n = ___
4. 2 : 3 = 10 : n n = ___
5. 90 : 6 = n : 18 n = ___