Apackaging plant uses a machine that can bottle 30 fluid ounces of shampoo in 12 seconds. how many fluid ounces of shampoo can be bottled per second

We have that

if the machine can bottle 30 fluid ounces of shampoo in > 12 seconds
X fluid ounces of shampoo in> 1 second
X=30/12=2.5 (I apply a rule of three)

the answer is 2.5 fluid ounces of shampoo

C+19÷-17=17c+(-1.11764706)=17c=.11764706)c=18.1176471