Helps needed with this diff qn

[miraclezdr]

a material decays at a rate proportional to its mass. there are 200mg of it initially, 5 hours later, it lost 10% of the original mass. let m denote the mass of remaining at anytime t. write the differential equation which describes the rate of change of m with respect to t, and solve the equation.

 

[Hootenanny]

a material decays at a rate proportional to its mass. there are 200mg of it initially, 5 hours later, it lost 10% of the original mass. let m denote the mass of remaining at anytime t. write the differential equation which describes the rate of change of m with respect to t, and solve the equation.

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[Feldoh]

a material decays at a rate proportional to its mass. -> Is giving you the basic differential equation.

there are 200mg of it initially, 5 hours later, it lost 10% of the original mass. -> Tells you how they are proportional.

You've just got to learn how to read the problems^^