13.5 kg of bronze was made by combining 8.1 kg of copper which costs $2.40/kg with 5.4 kg of tin which costs $7.40/kg. Find the cost per kg of the mixture.

The correct answer is $4.4

Explanation:

The cost per kilo of the bronze can be found by calculating the total price of the combination of metals and then dividing this by the total of bronze kilos. Now, let's first calculate the cost of copper and tin.

Copper:

$ 2.40 x 8.1 = $19.44

Tin:

$7.40 x 5.4 = $39.96

Total cost:

$19.44 + $39.96 = $59.4 (Total cost for the 13.5 kg of Bronze that combines tin and copper)

Finally, to find the price of a kilo of bronze divide the total cost into the kilograms of bronze.

$59.4 ÷ 13.5 = $4.4