Question

Sarah would like to make a 6 lb nut mixture that is 60% peanuts and 40% almonds. She has several pounds of a mixture that is 80% peanuts and 20% almonds and several pounds of a mixture that is 50% peanuts and 50% almonds.

a. What is the system that models this situation?
b. What is the solution to the system? How many pounds of the 80/20 mixture? How many pounds of the 50/50 mixture?

Answer 1

Answer: a. The system that models this situation is,

x + y = 6 , 8 x + 5 y = 36.

b. Solution is x = 2lb and y = 4lb

where x is the quantity of 80% of peanuts mixture mix with y quantity of 50% of peanuts mixture for making 60% of peanuts mixture.

Explanation:

Let x quantity of 80% of peanuts mixture mix with y quantity of 50% of peanuts mixture for making 60% of peanuts mixture.

Then According to the question,

x + y = 6 --------- (1)

And, 80 % of x + 50 % of y = 60 % of 6

⇒ 0.8 x + 0.5 y = 3.6

⇒ 8 x + 5 y = 36 --------- (2)

Where equation 1) and equation 2) are the required equation which models the given situation.

Now, 8 × equation 1)

We get, 8 x + 8 y = 48 ----------(3)

equation (3) - equation (2)

we get, 3 y = 12

⇒ y = 4

By putting the value of y in equation (2)

we get, x = 2

Thus, he mixed 2 lb of mixture 80/20 and 4 lb of mixture 50/50 for making 6 lb of 50/50 mixture.