To find the range of the total numbers of loads in both stores in both days we just need to add their minimum possible values and maximum possible values.
Then we have for the lower possible value of loads:
[tex]72+113+143+192=520[/tex]
and for the upper possible value of loads:
[tex]116+172+231+279=798[/tex]
Therefore the range for the total loads is:
[tex]520\leq k\leq798[/tex]
