Answer:
2B = R or B = R/2
Explanation:
We can write an expression where B is number of brownies and R is number of rice crispies. Since 80 is half the number of R then we can write R/2 as the number of brownies. B=R/2.
Since brownies are half the number of rice crispies, then twice as many brownies would need to sell to be the number of rice crispies. This is 2B = R.