In the morning, Marco sold 12 cups of lemonade for $3. By the end of the day, he had earned $9. How many cups of lemonade did he sell in all?

Kaycee wrote the proportion 12/3 = 9/c for this situation.

Identify the error and give two ways to write the proportion correctly.

In kaycee's she wrote 12/3 = 9/c, which was supposed to be 12/3 = c/9 or 3/12 = 9/c

The two ways to write the proportion are,

12/3 = c/9

or 3/12 = 9/c

Kaycee did not keep lemonade and dollars in corresponding positions in the ratios of the proportion. The proportion should be 12/3=c/9 or it could be written 3/12=9/c. Dollars should be in the same position and cups should be in the same position across ratios.

Step-by-step explanation:

10000000000% sure