Question

To find out how much baking soda Lisa should add to 9 lbs. of flour, we can use a proportion based on the amount she added to 6 lbs.

She adds 2 tsp of baking soda to 6 lbs of flour.

To determine how much baking soda to add for 9 lbs, we set up a ratio:

\[ \frac{2 \text{ tsp}}{6 \text{ lbs}} = \frac{x \text{ tsp}}{9 \text{ lbs}} \]

Cross-multiplying gives:

\[ 2 \times 9 = 6 \times x \] \[ 18 = 6x \]

Now, divide both sides by 6:

\[ x = \frac{18}{6} = 3 \text{ tsp} \]

So, Lisa should add 3 tsp of baking soda to 9 lbs. of flour.

The correct response is: 3 tsp.