Please overview the solution provided, it will only help you :)
the empty box weighs 2.75 kg
the store is packing 5 of the same laptops that weigh 1.65 kg each in said box
combined mass:
1.65*5=8.25kg
8.25+2.75=11 kg
it cost 40$ for the first 5kg and 3.15$ for EACH kg over kg
11kg>5kg
11-5=6
40+3.15(6)=58.90
Hence, the cost to ship the package was $58.90.
This problem may seem difficult, but essentially you just have to carefully read and work out the problem. Maths isn't so hard.