Please help me with this sum

In a school 2/3 of the students study a language of those who study a language 2/5 study french

Damon makes 20 cups of lemonade by mixing lemon juice and water. the ratio of lemon juice to water is shown in the tape diagram. lemon juice\text{lemon juice} lemon juice water\text{water} water how much lemon juice did damon use in the lemonade? cups

Ofis to ? o y=-3x-4o y=-3x+(-4)o y=-4 + 3xoy=-4-3x