820 US gallons in US customary cups
Result
The conversion result is: 820 US gallons is equivalent to 13120 US customary cups.[1]
Conversion formula
How to convert 820 US gallons to US customary cups?
We know (by definition) that: 1 usgallon ≈ 16 uscup.
We can set up a proportion to solve for the number of US customary cups.
1 usgallon / 820 usgallon ≈ 16 uscup / x uscup
Now, we cross multiply to solve for our unknown x:
x uscup ≈ (820 usgallon / 1 usgallon) * 16 uscup → x uscup ≈ 13120 uscup
Conclusion:
820 usgallon ≈ 13120 uscup
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Conversion in the opposite direction
The inverse of the conversion factor is that 1 US customary cup is equal to 7.6219512195122e-05 times 820 US gallons.
It can also be expressed as: 820 US gallons is equal to 1 / 7.6219512195122e-05 US customary cups.
Approximation
An approximate numerical result would be: eight hundred and twenty US gallons is about thirteen thousand, one hundred and twenty US customary cups, or alternatively, a US customary cup is about zero times eight hundred and twenty US 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.