Convert US fluid ounce to US beer barrel
Unit definitions
US fluid ounce
$\frac{1}{128}$ of a US liquid gallon is a US fluid ounce.
US beer barrel
The US beer barrel is defined as exactly $31$ US liquid gallons.
How to convert US fluid ounce to US beer barrel
$$\text{Volume}_{\text{bbl (beer)}} = \frac{\text{Volume}_{\text{oz (us)}}}{3968}$$
Examples
Example 1
Convert $40.0\ \text{oz (us)}$ to $\text{bbl (beer)}$.
$$\text{Volume}_{\text{bbl (beer)}} = \frac{40.0}{3968}$$
$$\text{Volume}_{\text{bbl (beer)}} = 0.010081$$
$$\therefore \ 40.0\ \text{oz (us)} = 0.010081 \ \text{bbl (beer)}$$
Example 2
Convert $70.0\ \text{oz (us)}$ to $\text{bbl (beer)}$.
$$\text{Volume}_{\text{bbl (beer)}} = \frac{70.0}{3968}$$
$$\text{Volume}_{\text{bbl (beer)}} = 0.017641$$
$$\therefore \ 70.0\ \text{oz (us)} = 0.017641 \ \text{bbl (beer)}$$
Example 3
Convert $100.0\ \text{oz (us)}$ to $\text{bbl (beer)}$.
$$\text{Volume}_{\text{bbl (beer)}} = \frac{100.0}{3968}$$
$$\text{Volume}_{\text{bbl (beer)}} = 0.025202$$
$$\therefore \ 100.0\ \text{oz (us)} = 0.025202 \ \text{bbl (beer)}$$
Example 4
Convert $140.0\ \text{oz (us)}$ to $\text{bbl (beer)}$.
$$\text{Volume}_{\text{bbl (beer)}} = \frac{140.0}{3968}$$
$$\text{Volume}_{\text{bbl (beer)}} = 0.035282$$
$$\therefore \ 140.0\ \text{oz (us)} = 0.035282 \ \text{bbl (beer)}$$
Example 5
Convert $170.0\ \text{oz (us)}$ to $\text{bbl (beer)}$.
$$\text{Volume}_{\text{bbl (beer)}} = \frac{170.0}{3968}$$
$$\text{Volume}_{\text{bbl (beer)}} = 0.042843$$
$$\therefore \ 170.0\ \text{oz (us)} = 0.042843 \ \text{bbl (beer)}$$