To find out how many cups of almonds Luis needs when he uses 3 cups of chocolate chips, we can set up a proportion based on the recipe.
The recipe states that for every 3/4 cup of chocolate chips, Luis needs 1/8 cup of almonds. We can express this as a ratio:
\[ \frac{1/8 \text{ cup almonds}}{3/4 \text{ cup chocolate chips}} \]
Next, to find out how many cups of almonds he needs for 3 cups of chocolate chips, we can set up the equation:
\[ \frac{1/8}{3/4} = \frac{x}{3} \]
Cross-multiplying gives:
\[ (1/8) * 3 = (3/4) * x \]
Calculating the left side:
\[ 3/8 = (3/4) * x \]
Now, to solve for \(x\), we can multiply both sides by \(4/3\):
\[ x = (3/8) * (4/3) \]
Calculating the right side:
\[ x = 1/2 \]
Thus, Luis will need 0.5 cups of almonds when he uses 3 cups of chocolate chips.
The answer is 0.5 cup.