The recipe makes 16 portions or servings of soup. Richard only wants 4 servings. This means he needs to divide each ingredient amount by 4. Note how 16/4 = 4.
So,
96/4 = 24 mL of oil is needed
240/4 = 60 grams of onions are needed
1.44/4 = 0.36 kilograms of potatoes are needed
1.61/4 = 0.4025 cups of milk are needed
Change "cups" to whatever other measurement unit is provided.