Answer:
4 capfuls of fertilizer
15 liters of water
Step-by-step explanation:
The instructions state that a  fertilizer/water ratio of 2 capfuls: 5 liters should be used.
Following that ratio, the amount of fertilizer required for 10 liters of water is:
[tex]\frac{F}{10}=\frac{2}{5} \\F=\frac{20}{5} = 4\ capfuls[/tex]
The amount needed is 4 capfuls of fertilizer.
The amount of water required for 6 capfuls of fertilizer is:
[tex]\frac{6}{W}=\frac{2}{5} \\F=\frac{30}{2} = 15\ liters[/tex]
The amount needed is 15 liters of water.