5 students consisting 2 girls and 3 boys are to be randomly assigned to 5 different chores of which 2 chores are light duty. What is the probability that:
a) the girls will be assigned to the light duty chores?
b) the girls will not be assigned to the light duty chores?

Question

5 students consisting 2 girls and 3 boys are to be randomly assigned to 5 different chores of which 2 chores are light duty. What is the probability that:
a) the girls will be assigned to the light duty chores?
b) the girls will not be assigned to the light duty chores?

anonymous · Answer

Probability= favorable number of events/total nummber events
combinations of 5 elements taken 2 by 2 = 5*4/2=10
combinations of 2 elements taken 2 by 2 = 1
a) 1/10
b) 9/10

anonymous · Answer

you mean 5C2 (from the group of people) and then multiply that with 2C2?

anonymous · Answer

devide positive combinations by total

anonymous · Answer

Thanks for replying btw. Wouldnt you go 2C2 (from the girls) instead of the entire group that goes 5C2? would the total be 5! (factorial)?

anonymous · Answer

but the order doesn't matter

anonymous · Answer

5C2 =5*4/2!

anonymous · Answer

oh i see and thats for the total probability?

anonymous · Answer

ya

anonymous · Answer

so i think the event would be 2C2 for choosing from the group of girls and from that we go 2C2 again when assigning them the tasks so 2C2.2C2 =1 hence 1/10?

anonymous · Answer

yes

anonymous · Answer

and for part B its just 1-1/10

anonymous · Answer

awesome thanks! are you good at perms and combs?

anonymous · Answer

don't remmeber much about it...:)

anonymous · Answer

oh ok but thanks for help!