So we want to know the number from which we take 25% and get 80. If the number we are looking for is x, then the equation to find that x would be: (25/100)*x=80 which says twenty five percent out of x is equal 80. So, x=(80*100)/25. And finally, x= 8000/25=320. So, 25% out of 320 is 80.
