21 imperial gallons in US customary cups
Result
The conversion result is: 21 imperial gallons is equivalent to 403.519174969631 US customary cups.[1]
Conversion formula
How to convert 21 imperial gallons to US customary cups?
We know (by definition) that: 1 imperialgallon ≈ 19.2151988080777 uscup.
We can set up a proportion to solve for the number of US customary cups.
1 imperialgallon / 21 imperialgallon ≈ 19.2151988080777 uscup / x uscup
Now, we cross multiply to solve for our unknown x:
x uscup ≈ (21 imperialgallon / 1 imperialgallon) * 19.2151988080777 uscup → x uscup ≈ 403.51917496963176 uscup
Conclusion:
21 imperialgallon ≈ 403.51917496963176 uscup
Conversion in the opposite direction
The inverse of the conversion factor is that 1 US customary cup is equal to 0.00247819697806247 times 21 imperial gallons.
It can also be expressed as: 21 imperial gallons is equal to 1 / 0.00247819697806247 US customary cups.
Approximation
An approximate numerical result would be: twenty-one imperial gallons is about four hundred and three point five one US customary cups, or alternatively, a US customary cup is about zero times twenty-one imperial gallons.
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.