Answer:
$193.67
Explanation:
Let x = shirts
Let y = trousers
Let z = hat
4x + 4y + 2z = 660
9x + 9y + 6z = 1399
Divide the second equation by 3.
3x + 3y + 2z = 466.33
Subtract both equations .
4x + 4y + 2z = 660
3x + 3y + 2z = 466.33
x + y = 193.67
So 1 shirt and 1 trouser will be $193.67