1 mile = 1.6 kilometers
multiply 40 mph by 1.6 = 64
car's rate = 64 kilometers per hour
multiply kilometers per hour by 4 = 256
car will travel 256 kilometers in 4 hours
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
Mike is driving 20 miles per hour
If he is driving 10 miles in 30 mins
(1/2 an hour) if you times both by two it tells you the MPH that Mike is driving.
Divide 2,800 by 25 which equals 112, there are 112 rows in total
