Answer: 
 ounces
Explanation:
Given : A box of ground nutmeg weighs 
 ounces. 
We can write 
 as 
 
 If there are 20 teaspoons of nutmeg in the box, then by Unitary method , we have
20 teaspoons =
 ounces
Divide both the sides by 20 , we get
1 teaspoon =
 ounces
i.e. 1 teaspoon =
 ounces
i.e. 1 teaspoon =
 ounces
Hence, one teaspoon of nutmeg weigh 
 ounces.