All of the angles measure less than 90 degrees
I think the answer is 27.43
18 choose 7
=C(18,7)
=18!/(7!(18-7)!)
=31824
OR
18 choices for first passenger,
17 choices for second passenger,
....
12 choices for 7th passenger,
so total = 18*17*16...12
but there are 7! ways to order the 7 passengers, so
number of groups
=18*17*16...12/7!
=31824 as well
The answer is Mary, Mary got 88% Ben got 86% and Jim got 85%
1+1 = 2 that is the answer
