Question 1049514
In order for one person to shake hands with all the other persons in the group, there will be 20 x 19 total handshakes per person. However, we can divide that number in half, since person A shaking hands with person B is the same as person B shaking the hands of person A. So, there are (20 x 19)/2, or 190 total handshakes. 190 x 3 seconds=570 seconds total. If the group is increased to 40 people, then the equation is ((40 x 39)/2) x 3, or 2340 seconds for all handshakes to be made. &#9786;&#9786;&#9786;&#9786;