Answer:
small: 6.25
large: 18.25
Step-by-step explanation:
Set the large boxes as x and the small boxes as y (The weight is the constant).
3x+5y=86
6x+2y=122
Now just solve the systems of equations using either substitution or elimination.
-6x-10y=-172 multiply the whole equation by -2 to eliminate
6x+2y=122, add the equations
-8y=-50
y= 6.25
Plug in y either equation:
3x+5(6.25)=86
3x=86-31.25
3x=54.75
x=18.25
Each small box weighs 6.25 kilograms, each large box weighs 18.25 kilograms, to check plug in the values to the other equation to see if they add up correctly.