With this information, you can calculate the quantity of kilograms 640 grams is equal to.
¿What is the inverse calculation between 1 kilogram and 640 grams?
Performing the inverse calculation of the relationship between units, we obtain that 1 kilogram is 1.5625 times 640 grams.
Which is the same to say that 640 grams is 0.64 kilograms.
Six hundred forty grams equals to zero kilograms. *Approximation
A kilogram is one times six hundred forty grams. *Approximation