Constraint 1:
Let the total number of running shoes be = R
Let the total number of leather boots be = L
As the given number of total shoes are 48,
The equations becomes,
R + L = 48............(1)
Constraint 2:
As running shoes are twice the leather boots, equation becomes,
R = 2L..............(2)
Putting the value of R from equation(2) in equation (1)
![2L+ L=48](https://tex.z-dn.net/?f=2L%2B%20L%3D48)
![3L=48](https://tex.z-dn.net/?f=3L%3D48)
![L=16](https://tex.z-dn.net/?f=L%3D16)
Now putting the value of L in equation(2)
R= 2L
R = ![2*16](https://tex.z-dn.net/?f=2%2A16)
R=32
Hence, Amanda needs 16 pairs of leather boots and 32 pairs of running shoes.