Answer :
Given :
1 batch of brownies required 15 cup of chocolate.
To Find :
If she has 8/10 cup of chocolate remaining, how many batches of brownies can Mary make.
Solution :
Ratio of cups to batch is :
[tex]R=\dfrac{15}{1}[/tex]
Let , batch produced from 8/10 cup of chocolate is x.
So ,
[tex]\dfrac{\dfrac{8}{10}}{x}=\dfrac{15}{1}\\\\x=\dfrac{8}{10\times 15}\\\\x=0.053\ batches[/tex]
Therefore , she can make 0.053 of a batch.
Hence , this is the required solution.