An elephant can eat 250 lb in 30 minutes, meaning her rate of consumption is
[tex]\frac{250lb}{30\min }[/tex]now 1 lb = 16 oz therefore,
250 lb = 250 * 16 oz = 4000 oz.
Therefore, the rate of consumption in ounces is
[tex]\boxed{\frac{4000\: lb}{30\min}=133.33.\text{. lb/min}}[/tex]which is our answer!