If a person bought 8 items and each item was priced at $4, that means the total amount spent was $32.

The person received 8 dollars in change. This means that the person payed 8 dollars more than what they spent. Well, we just found out how much they spent, so we can find out how much money the person gave the vendor.
Let p = amount of money paid by the person.


The person gave the vendor $40.
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
Square root is this 4 and -4 are square roots to 16 because 4^2= 16
distance = speed * time
the first bus speed = x
second bus = x - 12
the sum of distance = 765 miles
first distance = 6x
second distance = 6 (x -12)
6x + 6(x-12) = 765
x + x -12 = 127.5
2x = 139.5
x = 69.75 mi/h which is the faster bus
the second bus speed = 57.75 mi/h
There are many ways, but here is one:
x = 100
Since ‘x’ is 100 and we want 100 more, we just need to add ‘x’ to 623
Answer: x + 623 (Make sure you define your ‘x’ value)