What is the value of x?

You paint a 1/2 of a wall in 1/4 hour. how long will it take you to paint one wall

Having a hard time understanding this question (see attachment).

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