Question

adam prepares a meal of shrimp and brown rice. it must contain exactly 6 g of fat and 10 mg of iron. each 5oz serving of shrimp contains 2 g fat and 5 mg iron. each 1 cup of brown rice contains 6 g fat and 7 mg iron. how many servings of shrimp and brown rice should be in the meal?

Answer 1

Adam needs 9/8 of a 5oz serving of shrimps (which equals to 5.625 oz) and 5/8 of a cup of brown rice (which is around 10 tablespoons).

Step-by-step explanation:

You are given:

every serving of shrimp contains 2g of fat and 5mg of iron;

every serving of rice contains 6g of fat and 7mg of iron;

each meal should have 6g of total fat and 10mg of total iron.

You need to set a system of equation: let's call

s = quantity of shrimps

r = quantity of rice

The equation for the total fat will be: the quantity of fat in the serving of shrimps plus the quantity of fat in the serving of rice must be equal to 6g

2s + 6r = 6 (1)

Similarily:

the quantity of iron in the serving of shrimps plus the quantity of iron in the serving of rice must be equal to 10g

5s + 7r = 10 (2)

In order to solve the system, solve for s in equation (1):

s = (6-6r)/2 = 3 - 3r (3)

Substitute in equation (2):

5(3 - 3r) + 7r = 10

and solve for r:

15 - 15r + 7r = 10

8r = 5

r = 5/8

Substitute the value of r in equation (3):

s = 3 - 3×5/8 = 9/8

Therefore Adam would need 9/8 of a 5oz serving of shrimps and 5/8 of a 1 cup of brown rice for each meal.