Hats Party
Probability
Level
1
15 people attended a party. 11 people were wearing black hats and 4 people were wearing white hats. If all the people in white hats shook all the people in black hats hands, how many hand shakes would there be?
The answer is 44.
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
1 solution
Each of 4 people wearing white hats shook hands with 11 people wearing black hats. That means, one person wearing white hat would make 11 handshakes. As the people wearing black/ white hats did NOT shake hands with one another, and they shook only 1 time per person, we shall have: 4 x 11 = 44 . Easy one.