How to convert 81 imperial gallons to US dry barrels?
We know (by definition) that:
We can set up a proportion to solve for the number of US dry barrels.
Now, we cross multiply to solve for our unknown :
Conversion in the opposite direction
The inverse of the conversion factor is that 1 US dry barrel is equal to 0.31400507972541 times 81 imperial gallons.
It can also be expressed as: 81 imperial gallons is equal to US dry barrels.
An approximate numerical result would be: eighty-one imperial gallons is about three point one eight US dry barrels, or alternatively, a US dry barrel is about zero point three one times eighty-one imperial gallons.
 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.