So there are 8 students, therefore each student gets 1/8 of
the cake.
Since only 3/4 of a cake is available, they will each get
1/8 of 3/4.
We can find this by
multiplying 1/8 and 3/4.
To get the answer, we multiply the numerators together and
the denominators together which gives us:
(1*3)/(8*4) = 3 / 32 = 0.09375
So each student only get 3 / 32 of the cake.
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 :

Let , batch produced from 8/10 cup of chocolate is x.
So ,

Therefore , she can make 0.053 of a batch.
Hence , this is the required solution.
30% off means u r actually paying 70%..
70% of 33...turn ur percent to a decimal..." of " means multiply
0.70 * 33 = 23.10 <== this is the price after the discount