21 milliliters in US quarts
Result
The conversion result is: 21 milliliters is equivalent to 0.0221904523980845 US quarts.[1]
Conversion formula
How to convert 21 milliliters to US quarts?
We know (by definition) that: 1 ml ≈ 0.00105668820943259 usquart.
We can set up a proportion to solve for the number of US quarts.
1 ml / 21 ml ≈ 0.00105668820943259 usquart / x usquart
Now, we cross multiply to solve for our unknown x:
x usquart ≈ (21 ml / 1 ml) * 0.00105668820943259 usquart → x usquart ≈ 0.02219045239808439 usquart
Conclusion:
21 ml ≈ 0.02219045239808439 usquart
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Conversion in the opposite direction
The inverse of the conversion factor is that 1 US quart is equal to 45.064426 times 21 milliliters.
It can also be expressed as: 21 milliliters is equal to 1 / 45.064426 US quarts.
Approximation
An approximate numerical result would be: twenty-one milliliters is about zero point zero two US quarts, or alternatively, a US quart is about forty-five point zero six times twenty-one milliliters.
Footnotes
[1] The precision is 15 significant digits (fourteen digits to the right of the decimal point).
Results may contain small errors due to the use of floating point arithmetic.