Question

solve mixture prolems whith proportion practice

Answers

GPT-4o mini
Sure! Mixture problems often involve combining different elements with known properties to achieve a desired outcome. These problems can typically be solved using proportions. Here are a few examples along with their solutions.

### Example 1: Mixing Two Solutions

**Problem:**
You have a 30% salt solution and a 50% salt solution. How many liters of each solution do you need to mix together to obtain 12 liters of a 40% salt solution?

**Solution:**
Let \( x \) be the liters of 30% salt solution and \( 12 - x \) be the liters of 50% salt solution.

Set up the equation based on the total amount of salt in the final mixture:

\[
0.30x + 0.50(12 - x) = 0.40(12)
\]

Expand and simplify:

\[
0.30x + 6 - 0.50x = 4.8
\]

Combine like terms:

\[
-0.20x + 6 = 4.8
\]

Subtract 6 from both sides:

\[
-0.20x = -1.2
\]

Divide by -0.20:

\[
x = 6
\]

So, you need 6 liters of the 30% solution. Now, the amount of the 50% solution is:

\[
12 - x = 12 - 6 = 6 \text{ liters}
\]

### Answer:
You need 6 liters of the 30% solution and 6 liters of the 50% solution.

---

### Example 2: Mixing Two Grades of Cement

**Problem:**
You want to create 100 kg of a mixture that is 70% cement. You have a cement that is 50% cement and another that is 90% cement. How much of each type do you need?

**Solution:**
Let \( x \) be the kg of the 50% cement, and \( 100 - x \) be the kg of the 90% cement.

Set up the equation based on the total amount of cement in the final mixture:

\[
0.50x + 0.90(100 - x) = 0.70(100)
\]

Expand and simplify:

\[
0.50x + 90 - 0.90x = 70
\]

Combine like terms:

\[
-0.40x + 90 = 70
\]

Subtract 90 from both sides:

\[
-0.40x = -20
\]

Divide by -0.40:

\[
x = 50
\]

So, you need 50 kg of the 50% cement. Now, the amount of the 90% cement is:

\[
100 - x = 100 - 50 = 50 \text{ kg}
\]

### Answer:
You need 50 kg of the 50% cement and 50 kg of the 90% cement.

---

### Example 3: Mixing Two Drinks

**Problem:**
A bartender has a drink that is 20% alcohol and another that is 60% alcohol. How many liters of each should he mix to create 10 liters of a drink that is 40% alcohol?

**Solution:**
Let \( x \) be the liters of the 20% alcohol drink, and \( 10 - x \) be the liters of the 60% drink.

Set up the equation based on the total amount of alcohol in the final mixture:

\[
0.20x + 0.60(10 - x) = 0.40(10)
\]

Expand and simplify:

\[
0.20x + 6 - 0.60x = 4
\]

Combine like terms:

\[
-0.40x + 6 = 4
\]

Subtract 6 from both sides:

\[
-0.40x = -2
\]

Divide by -0.40:

\[
x = 5
\]

So, you need 5 liters of the 20% alcohol drink. Now, the amount of the 60% drink is:

\[
10 - x = 10 - 5 = 5 \text{ liters}
\]

### Answer:
You need 5 liters of the 20% alcohol drink and 5 liters of the 60% alcohol drink.

---

These examples illustrate how to set up and solve mixture problems using proportions. If you have a specific problem in mind or need more practice examples, feel free to ask!