Answer :

LammettHash

You're given two points of the form [tex](x,y)[/tex] where [tex]x[/tex] and [tex]y[/tex] are inversely proportional. That is, there is some constant [tex]k[/tex] for which

[tex]xy=k[/tex]

Use the first point to find [tex]k[/tex]:

[tex]4\cdot19=k\implies k=76[/tex]

Now you can find the other point's [tex]y[/tex]-coordinate:

[tex]10y=76\implies y=\dfrac{76}{10}=\dfrac{38}5[/tex]