Question

4. A local pizzeria offers 13 toppings for their pizzas and you can choose any 3 of them for one fixed price. How many different types of pizzas can you order with 3 toppings? (1 point)

Answer 1

It would be (13 C 3). Do you know how to do combinations?

Answer 2

Aright with combinations you are choosing r ways from the total n ways. In this case. N is the total amount of toppings. R is the amount that you use each time

Answer 3

So r is 3. And the formula for nCr is n!/(n-r)!)(r!)

Answer 4

yes do you know what a factorial (!) is?

Answer 5

no, my techer explains nothing!:/

Answer 6

alright. so in this case n! would be 12!
12! is an equivalent of 12x11x10x9x8x7x6x5x4x3x2x1

Answer 7

and (n-r)! would be (12-3)!=9!

Answer 8

im still confused.. this is my worst subject :/

Answer 9

so the 12! in the numerator would cancel with the 9! in the denominator. and become 12x11x10

Answer 10

so then i would multiply those and get the the answer?

Answer 11

\[\frac{ 12! }{ (12-3)!(3!) }\]

Answer 12

so the 12! is 12x11x10x9x8x7x6x5x4\[\frac{ 12x11x10x9x8x7x6x5x4x3x2x1 }{ 9x8x7x6x5x4x3x2x1 (3!)}\]

Answer 13

now do you see that everything from 9 down can cancel out?

Answer 14

This would equal to:\[\frac{ 12x11x10 }{ 3x2x1 }\]

Answer 15

o okay

Answer 16

Are you taking AP statistics?

Answer 17

no,algebra

Answer 18

Wow i learned this in statistics. Does it make sense now?

Answer 19

a little but not really .. lets just say i dont think I could pass the test or come any where near :/

Answer 20

if you want make me a fan...i need to go.

Answer 21

this is what i have to chose form
87,178,291,200
14
1
17,297,280

Answer 22

12*

Answer 23

I got 220...

Answer 24

ok thank you for your help I will try and figuer this out :/

Answer 25

Alright one more thing. I used combinations because order does not matter. This means that ABC are the same as ACB. So a pizza with 3 toppings is the same as a pizza with the same 3 toppings spread around differently

Answer 26

okay thanks :)

Answer 27

Sure and i can't believe that in algebra one permutations and combinations are taught. Well i g2g cya!

Answer 28

hey i answerd 286 and got it correct :)

Answer 29

My bad it was 13 as n so it would be...\[\frac{ 13x12x11x }{ 3x2x1 }\]

Answer 30

so \[\frac{ 13! }{ 10!(3!) }\]

Answer 31

anyway cya i really g2g