What is the location of the other point?

How much orange juice do you need to make 2 servings of lemony orange slush?

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of

Can someone show me step by step how to do this?