Answer
An adult's body contains approximately 6.5 liters of blood.
Work Step by Step
If the human body contained 6.5 kiloliters of blood, there would be enough blood to fill 6500 one-liter bottles. Clearly, this volume of blood is much greater than the whole human body. Therefore, this volume is much too large.
If the human body contained 6.5 milliliters of blood, there would less than two teaspoons of blood in the body. Clearly this amount of blood is too small.
If the human body contained 6.5 liters of blood, there would be enough blood to fill 6.5 one-liter bottles. This seems like a reasonable amount of blood in the human body.
An adult's body contains approximately 6.5 liters of blood.
