Hint:
Let the weight of the blue box be X
Let the weight of the orange box be Y
Let the weight of the purple box be Z
Orange Box + Blue Box = 28
So, Y + X = 28
--> Y = 28 - X
Orange Box + Purple Box = 32
So, Y + Z = 32 -----(1)
Blue Box + Purple Box = 38
X + Z = 38
Z = 38 - X
Substituting in (1)
28 - X + 38 - X = 32
66 - 2X = 32
34 = 2X
17 = X
So, Blue box = 17 Kg
Now, substitute the value of X in equation to find the weight of orange and purple box and find the answer
