a manufacturing company has 15% cobalt ,25% led and 60% of copper. if 5kg of led is used in a mixture how much copper we need to use	Pick one:
A) 12 kg
B) 13 kg
C) 22 kg
D) 14 kg
E) 15 kg

Rationale: 25 % = 5 kg 100 % = 20 kg 60 % of 20 kg = 12 kg 12 kg answer : a
Answer: A