For a barrel of oil, the first time you pour 1 / 5, the second time you pour 15 kg, the third time you pour 1 / 3, and there is 8 / 3 kg left. How many kg of this barrel of oil is there No, I'll give him 20 on a first come, first served basis

For a barrel of oil, the first time you pour 1 / 5, the second time you pour 15 kg, the third time you pour 1 / 3, and there is 8 / 3 kg left. How many kg of this barrel of oil is there No, I'll give him 20 on a first come, first served basis

One fifth of a barrel of oil is poured out in the first time, 15 kg is poured out in the second time, 1 / 3 is poured out in the third time, and there are 8 and 1 / 3 kg left,
This barrel of oil: (15 + 8 + 1 / 3) / (1-1 / 5-1 / 3) = 50kg

A barrel of oil, the first pour out 25 kg, the second pour out 20 kg, there are still 28 kg in the barrel. How many kg is the barrel of oil?

(20 + 28) / (1-25) = 48 / 35 = 80 (kg) a: this barrel of oil used to be 80 kg

A barrel of oil, the first time you pour out 1 / 8 of this barrel of oil, the second time you pour out 1 / 4, there are 15 kg left. How many kg of this barrel of oil?

Total = 15 ÷ (1-1 / 8-1 / 4) = 15 ÷ (5 / 8) = 24 kg;
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For a bucket of soybean oil, the first time you pour out 1 / 8 of this bucket of oil, the second time you pour out 1 / 4 of this bucket of oil, there are 35 kg left. How many kg does this bucket of soybean oil weigh?

35 / (1-1 / 8-1 / 4) = 56 kg