A girl wants to make a 50 ml of 5% lemon solution mixing a quantity of 3% lemon type 1 solution with a 7% type 2 lemon solution. Find the quantities of each concentration she has to use.
1
25 ml and 25 ml
2
35 ml and 20 ml
3
25 ml and 40 ml
4
20 ml and 20 ml
5
20 ml and 35 ml