Question

7. In 2 kg mixture of copper and aluminum, 30% is copper. How much aluminum
powder should be added to the mixture so that the quantity of copper becomes
20%?
(A)'900 gms (B) 800 gms (C) 1000 gms (D) 1200 gms​

Answer 1

Answer:

Mixture = 2 kg

Copper = 30 % of mixture

Aluminium = 70 % of mixture

= 70 / 100 × 2000 g

= 1400g

= 1.4 kg

Aluminium = 1.4 kg

so the amount of copper becomes 600g ...