Problema Solution

Jamaal is planning to invest up to $22000 in City Bank or State Bank. He wants to invest at least $3000 in City Bank, but not more than $7000; since State Bank does not insure more than $17000, he wants to invest no more than this amount in State Bank. The interest at City Bank is 4%, and the interest at State Bank is 7%. How much should he invest in each bank to earn the most interest?

Answer provided by our tutors

let


x = the money invested in City Bank, x>= 0

y = the money invested in State Bank, y >= 0


x + y = 22000


3000<= x


x < 7000


y > 17000


are the constrains


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the corner points are (7,000, 15,000) and (3,000, 17,000)


the objective function is F(x , y) = 0.04x + 0.07y


F(7,000, 15000) = 0.04*7000 + 0.07*15000 = 1330


F(3,000, 17,000) = 0.04*3000 + 0.07*17000 = 1310


he should invest $7,000 in City Bank and $15,000 at State bank.