MediumLinear systems

Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) §11.4 Matrices and Linear Equations, #21 · Linear Algebra · Linear systems

Suppose … billion people live in the U.S

Suppose $x = \frac{1}{4}$ billion people live in the U.S. and $y = 5$ billion live outside. If 4 per cent of those inside move out and 2 per cent of those outside move in, find the populations $d_{1}$ inside and $d_{2}$ outside after the move. Express this as a matrix multiplication $A u = d$ (and find the matrix).

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Gilbert Strang, Calculus, 3rd edition (Wellesley-Cambridge Press; MIT OpenCourseWare RES.18-001) · §11.4 Matrices and Linear Equations, #21

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