The answer is a. here’s a picture that hopefully helps explain the reasoning/work
We know that
The formula for combinations is
C=n!/[(n-r)!*r!]
where
n is the total number of objects you choose from
r is the number that you choose to arrange
in this problem
n=15 students
r=4 students
C=15!/[(15-4)!*4!]-----> C=15!/[11!*4!]---> (15*14*13*12*11!)/(11!*4*3*2*1)
C=(15*14*13*12)/(24)----->C=1365
the answer is
1365
5x6 = 30 divided in half because its a triangle
=15
2x3 = 6
15-6 = 9
He spent $36 on safety equipment.
The total cost each time was $11, meaning he had to pay 9 times for each skate session. 4x9=36! ( 7x9= 63 so if you add 36 you'll get 99 just as a way of checking)
Do you watch/read pandora hearts?
The sale price of the jeans would be $73.09
