Question

How many kilograms of coffee worth 40/kg must be mixed with coffee worth $11/kg to give 12kg of coffee worth $9.50/kg

Answer 1

Answer:

0.62kg

Step-by-step explanation:

Let

x = 40/kg coffee

y = 11/kg coffee

two equations can be derived from the question

x + y = 12 equation 1

40x + 11y = 114 (9.5 x 12)  equation 2

multiply equation 1 by 11

11x + 11y = 132 equation 3

subtract eqn 3 from eqn 2

29x = 18

divide both sides of the equation by 29

x = 0.62kg