Works out how fast a diver uses gas at depth and how long a supply will last. Consumption is the surface rate times the absolute pressure.
The formula: Consumption = rate x absolute; duration = gas / consumption. Change any box and the full working updates. For study only, never for dive planning.
The IMCA ADS, BDS and LST papers ask this as a four-option question, with a calculator on screen. A free account gives you 15 practice questions for each exam, each with the worked answer and the document it comes from.