A tank contains 150 liters of fluid in which 20 grams of salt is dissolved. Pure water is then pumped into the tank at a rate of 3 L/min; the well-mixed solution is pumped out at the same rate. number A(t) of grams of salt in the tank at time t. A(t) = 10e g

The product of two numbers is equal to the product of two other numbers. Three of these four numbers are 3, 4 and 12. The number of possible values of the fourth number is

100x + 50y + 50z = 10,500 10x + 100y = 1,500 200x + 50y + 150z = 25,500 solve for each variable

The sum of  a two digit numbers and the number obtained by receiving the order of its digits is 165 . if the digits differ by 3 find the number ?