Answer: 7 hours 12 minutes
Explanation:
Let he needs x hours to make 1 kg of meat.
Therefore, time taken in making 5 kg of meat = 5 × x = 5x hours.
But, According to the question,
He needs 12 hour to cook 5 kg of meat.
Thus, 5 x = 12
⇒
( By dividing both sides by 5 )
⇒ He needs
hours to make 1 kg of meat.
⇒ The time taken to cook 3 kg of meat =

=
hours ⇒ 7 hours 12 minutes
Hence, He needs 7 hours 12 minutes time to cook 3 kg of meat.