A rocket contained 467,000 kilograms (kg) of propellant before launch. Exactly 21 seconds after launch, 362,105 kg of this propellant remained. On average, approximately how much propellant, in kg,did the rocket burn each second after launch

Explanation

Choice A is correct. It's given that the rocket contained 467,000 kilograms (kg )of propellant before launch and had 362,105 kg remaining exactly 21 seconds after launch. Finding the difference between the amount, in kg, of propellan before launch and the remaining amount, in kg, of propellant after launch gives the amount, in kg, of propellant burned during the 21 seconds: 467,000 362,105 104,895 - = . Dividing the amount of propellant burned by the number of seconds yields 104,89521 = 4,995. Thus, an average of 4,995 kg of propellant burned each second after launch.