Jennie is making popcorn. The recipe for 1/2 cup of butter, 3 tablespoons of kernels, and 1 teaspoon of salt. If she uses 10 tablespoons of kernel, how much butter does she need? Round your answer to the nearest hunredth

1.67

1.66

1.50

3.33

1 answer

To determine how much butter Jennie needs for 10 tablespoons of kernels, we first need to establish the ratio of kernels to butter in the original recipe.

The original recipe uses:

  • 1/2 cup of butter
  • 3 tablespoons of kernels

First, we convert the butter measurement to tablespoons, knowing that 1 cup = 16 tablespoons:

1/2 cup of butter = 8 tablespoons

The ratio of butter to kernels in the original recipe is:

\[ \text{Butter} : \text{Kernels} = 8 \text{ tablespoons} : 3 \text{ tablespoons} \]

To find out how much butter is needed for 10 tablespoons of kernels, we set up a proportion based on the original ratio:

\[ \frac{8 \text{ tablespoons of butter}}{3 \text{ tablespoons of kernels}} = \frac{x \text{ tablespoons of butter}}{10 \text{ tablespoons of kernels}} \]

Cross-multiplying gives us:

\[ 8 \times 10 = 3 \times x \]

So,

\[ 80 = 3x \]

Now, we solve for \(x\):

\[ x = \frac{80}{3} \approx 26.67 \text{ tablespoons of butter} \]

To convert this back to cups, we divide by 16 (since there are 16 tablespoons in a cup):

\[ \text{Butter in cups} = \frac{26.67}{16} \approx 1.6667 \text{ cups} \]

Rounding to the nearest hundredth gives:

\[ \text{Butter needed} \approx 1.67 \text{ cups} \]

Thus, the answer is 1.67.