Question

differential equations please solve fast

4.)(25 points) Consider two tanks, labeled tank A and tank B. Tank A contains 100 gallons of solution in which is dissolved 20 lbs of salt. Tank B contains 200 gal of solution in which is dissolved 40 lbs of salt. Pure water flows into tank A at a rate of 5 gal/min. A drain at the bottom of Tank A allows the solution to leave at a rate of 5 gal/min and flow directly into tank B. A drain at the bottom of tank B allows the solution to leave tank B at a rate of 2.5 gal/min. Find the salt content in tank B when the tank contains 250 gallons of solution?

Answer 1

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2 400 5 t Rot &ott ent. change ( ) go-+t 20 50. e-t120 80+ t dt 80忙丿 七 So+t this ttauhing ơnta ue have to find me ente orton jtt) -t-t/20 Cott

- 80+t J(t) 80个 80十t Sott ytt) 20 (804t)e Fott(Kv+t) 2D -t (Fo+t) (So+t)

20 ナ &o SO ?o) (Ho) - 2000 A A - SR00 tS200 20 u00 e y(t) - - 20.e Sutt- gott S2.00 804-25- lo 20 20 2 20 20 O (20)F -20 e 8O+M

-HOO (20) - -20e - S200 tao Iao -1