A family needs to cross a river in a small raft. Father weighs 90kg, mother weighs 80kg, son
weighs 60kg, daughter weighs 40kg, and they have
a 20kg bag. The raft cannot bear a load heavier
than 100kg. How can they all get to the other side
with their bag?

they drown and realize they are sad poor people from a third world country with no bridges

Step-by-step explanation:

so basically you can take more than one trip you can take the mother and the bag at the same time

Step-by-step explanation:

and then you can get the daughter in the son at the same time and then for the final trip you take the father by himself

6.9

step-by-step explanation:

simple math really

6 1/2 times 0.6 = 3.9

but if you are just doing 6 and not 6 1/2 then the answer is 3.6