Countries where pounds and ounces are commonly used:
United States of America (USA) , South Africa, United Kingdom (UK), Eire (ROI), India, Canada, Australia and the Commonwealth of Nations.
A rough guide when you are measuring liquids: 1 ml of water equals 1 gram, 1 litre of water weighs approx 1 kilo - other liquids may differ.
Converting grams into ounces, the maths
Times grams by 0.0353 to convert grams into ounces
2295 g = 81.0135 oz
Answer = int(2295 * .0353) [81 oz]
Here are the calculations used to convert ounces to pounds and ounces
oz_start = 81
lb_calc = int(oz_start/16) [therefore lb_calc == 5 lb]
oz_calc = 81 - (lb_calc * 16) [therefore oz_calc = 1 oz]
Answer = lb_calc, oz_calc [5 lb, 1 oz]
Wikipedia links covering units of mass show/hide