Y = kx is the direct variation formula. They are giving y = 48n AFTER they have plugged in a value for x. The value plugged in for x is 16n. To find 'k' we must divide 48n by 16n.
48n/16n = 3 So k = 3.
The equation is therefore y = 3x
The 3rd answer, when m is next to a number it means “per” for something like per second or (in this case) per minute, etc...
Solution:
we are given that
A jury pool consists of 50 potential jurors.
Wee have been asked to find the number of ways can a jury of 12 be selected.
As we know from the concept of combination that r person can be selected out of n in ncr ways. where

Now substitute the values we get

Hence the required number of ways is 121399651100