. A recipe for cookies calls for 2/3 of a cup of sugar per batch of cookies. Elena used 5 and 1/3 cups of sugar to make multiple batches of cookies. How many batches did she make? Consider drawing a model to help you solve the problem.

8 batches
Step-by-step explanation:
To get the number of batches she made, we can just use proportion to solve it. But first, we need to convert 5 1/3 to improper fraction
5 1/3 = 16/3
Then we can now use the proportion to solve
2/3 cups = 1 batch
16/3 cups = x (note:5 1/3=16/3)
cross multiply
2/3 × x = 16 /3
2x/ 3 = 16/3
we need to make x the subject of the formula, to do that we will multiply each side of the equation by 3/2
2/3 × 3/2 x = 16/3 × 3/2
6x /6 = 48 / 6
x = 8
Therefore she made 8 batches of cookies.

B. 8 batches of cookies

Step-by-step explanation:  

We need to solve for x.

5 1/3 = 16/3

Use proportions to solve

2/3 cups = 1 batch of cookies

16/3 cups = x

Use cross multiplication

2/3 × x = 16 /3

2x/ 3 = 16/3

Multiply each side of the equation

2/3 × 3/2 x = 16/3 × 3/2

6x /6 = 48 / 6

x = 8

He used a stratified sampling technique