Question

9. 60 kg of an alloy of Zinc and Aluminium contains 80% of Zinc. How much Zinc must be
melted into it to make the alloy contains 85% of Zinc ?​

Answer 1

Answer:

20

Step-by-step explanation:

80% Zinc & 20% Aluminium

12 kg Al, 48 kg Zn

Let the amount of melted Zn that will be added is x

(x + 48)/(x+60) *100 = 85

(x + 48)/(x+60) = 17/20

20x + 960 = 17x + 1020

3x = 60

x = 20

So, adding 20 kg Zinc should be enough .

Answer 2

Answer:20

Step-by-step explanation:

80% Zinc & 20% Aluminium

12 kg Al, 48 kg Zn

Let the amount of melted Zn that will be added is x

(x + 48)/(x+60) *100 = 85

(x + 48)/(x+60) = 17/20

20x + 960 = 17x + 1020

3x = 60

x = 20

So, adding 20 kg Zinc should enough

Step-by-step explanation: