Question

There is a mixture of 120 Kg copper
and Zinc, in which 80% is copper.
How much Zinc must be added to the
mixture, so the new mixture contains
40% Copper.​

Answer 1

Answer:

Amount of Zinc added in new mixture = 24 kg

Step-by-step explanation:

Given :

Mixture of copper and Zinc is = 120 kg

Percentage of copper = 80%

Percentage of Zinc = 100%-80% = 20%

To find :

How much should be added Zinc to the new mixture to become 40% .

Concept :

First find amount of Zinc in the mixture . After that find the amount of Zinc in new mixture .

Then , subtract the amount of Zinc in old mixture from the amount of Zinc in the new mixture .

So , the equation will form like this -:

$\boxed{\sf{M=(\dfrac{40\%}{100\%}\times120kg)-(\dfrac{20\%}{100\%}\times120kg})}$

Where,

M = Mixture of Zinc added

Solution :

$:\implies\sf{M=(\dfrac{40\%}{\cancel{100}\%}\times\cancel{120kg})-(\dfrac{20\%}{\cancel{100}\%}\times\cancel{120kg})}$

$:\implies\sf{M=(40\%\times1.2)-(20\%\times1.2)}$

$:\implies\sf{M=48kg-24kg}$

$:\implies\sf{M=24kg}$

So , the amount of Zinc added in the new mixture is 24 kg .