Question

A shopkeeper mixed coffee powder worth $2.50 per kg with coffee powder worth $3.50 per kg, and sold 20 kg of the mixture at $2.80 per kg. Find the weights of the 2 grades of coffee powder that he mixed together. Explain clearly your steps of solving it.

Answer 1

Let the amount of the $2.50 coffee be x kg
then the amount of the $3.50 coffee will be 20-x kg

2.5x + 3.5(20-x) = 2.8(20) = 56
times 10
25x + 35x(20-x) = 560
25x + 700 - 35x = 560
-10x = -140
x = 14

He should mix 14 kg of the $2.50 and 6 kr of the $3.50 coffee.

Answer 2

Weight of $2.50 coffee be x kg
Weight of $3.50 coffee be y kg
2.5x+3.5(20-x)= 2.8(20)
2.5x+700-3.5x=56
-x=56-70
x=14
14 kg of $2.50 coffee
20-14kg of $3.50 coffee
Thus
14 kg of $2.50 coffee
6kg of $ 3.50 coffee

Answer 3

Thank you. It was a great help.

Answer 4

THANKS

Answer 5

y did we multiply it by ten