A barrel of oil is used 25% in the first day and 10 kg in the second day. Half of it is left. How many kg is the barrel of oil?

A barrel of oil is used 25% in the first day and 10 kg in the second day. Half of it is left. How many kg is the barrel of oil?

10 (1-12-25) = 10 / 110 = 100 (kg) a: this barrel of oil used to be 100 kg

A barrel of oil, if one fourth of the oil is poured out, weighs 19 kg. If one third of the oil is poured out, it weighs 17 kg. How many kg does the barrel weigh?

Let the weight of this barrel of oil be XKG. From the first condition, the weight of the barrel is 19-x (1-1 / 4) kg. From the second condition, the weight of the barrel is 17-x (1-1 / 3) kg. Thus, the equation 19-x (1-1 / 4) = 17-x (1-1 / 3) is established. The solution is x = 24, so the weight of oil is 24kg