You would do 0.25x (x is the unknown total number)=19. It is because of is a multiply sign, so 0.25*x=19. Divide both sides by 0.25 and you get 76 as your answer.

HFadhila

25% OF WHAT = 25% OF X = .25 OF X = .25X
.25X = 19
X = 19 DIVIDED BY .25
X = 19 DIVIDED BY 1/4
X = 19 X 4
X = 76