Hello there,
The amount of blood in the human body is generally equivalent to 7 percent of body weight. The average adult weighing 150 to 180 pounds (60 to 80 kgs) should have about 1.2 to 1.5 gallons of blood in their body. This is about 4,500 to 5,700 mL. The average amount of blood in the body is an estimate because it can depend on how much the person weighs, their gender, and even where they live.
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