this is a permutations problem
number of permutations for ONE pizza:
8P3 =
8! divided by (8 - 3)! = 336
multiply this by 3 since there are 3 types of crust
336 x 3 = 1008
hope this helps!!
permutations question
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Why is this a permutation and not a combination problem?
For me the solution is 3x 8C3.....
For me the solution is 3x 8C3.....
800guy wrote:this is a permutations problem
number of permutations for ONE pizza:
8P3 =
8! divided by (8 - 3)! = 336
multiply this by 3 since there are 3 types of crust
336 x 3 = 1008
hope this helps!!
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one_pacifist
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hi all 
new to permutations and combinations topic, so need help on this ....
q) A set of 6 questions contains true /false type questions.
Maximum how many students can take the test if all the students answer differently from others and must attempt all the questions ?
a gud explanation on answer will help a lot!!!!!!
new to permutations and combinations topic, so need help on this ....
q) A set of 6 questions contains true /false type questions.
Maximum how many students can take the test if all the students answer differently from others and must attempt all the questions ?
a gud explanation on answer will help a lot!!!!!!
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Night reader
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8P3 * 3!=8!/(8-3)! *3=1008saigopal7 wrote:Pat's pizza offers thick,thin, or deep-dish style crust.There are 8 choices for toppings.
In how many ways can u choose a pizza with three different toppings?
Ans:1008
call pizzas: thick-x,thin-y, deep-dish-z
x, y or z can be chosen in 8 ways as the first order
x, y or z can be chosen in 7 ways
x, y or z can be chosen in 6 ways
(8*7*6) *3=1008
Last edited by Night reader on Sat Feb 05, 2011 1:12 am, edited 1 time in total.
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rohu27
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Nightreader,
Please clarify this one.
we are asked to choose a single pizza wth 3 diff toppings.
no. of ways to choose 3 toppings out of 8 is 8c3.
as the no. of crusts are 3, total combnations are: 3*8c3=168 combinations.
or is it tht we need to consider a thin crust pizza wth ABC toppings diff frm a thin crust pizza wth BAC toppgs?
Totally confused
Please clarify this one.
we are asked to choose a single pizza wth 3 diff toppings.
no. of ways to choose 3 toppings out of 8 is 8c3.
as the no. of crusts are 3, total combnations are: 3*8c3=168 combinations.
or is it tht we need to consider a thin crust pizza wth ABC toppings diff frm a thin crust pizza wth BAC toppgs?
Totally confused
Night reader wrote:8P3 * 3!=8!/(8-3)! *3!=2116 this should be the correct answer in realitysaigopal7 wrote:Pat's pizza offers thick,thin, or deep-dish style crust.There are 8 choices for toppings.
In how many ways can u choose a pizza with three different toppings?
Ans:1008
or call pizzas: thick-x,thin-y, deep-dish-z
x, y or z can be chosen in 8 ways as the first order
x, y or z can be chosen in 7 ways
x, y or z can be chosen in 6 ways
(8*7*6) *3!=2116
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Night reader
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I've edited the previous solution; the problem doesn't explicitly state the topping order, so I assumed that ABC is different from BAC 
if the topping order doesn't matter than 3*6C3 if it does matter then 3*6P3
if the topping order doesn't matter than 3*6C3 if it does matter then 3*6P3
rohu27 wrote:Nightreader,
Please clarify this one.
we are asked to choose a single pizza wth 3 diff toppings.
no. of ways to choose 3 toppings out of 8 is 8c3.
as the no. of crusts are 3, total combnations are: 3*8c3=168 combinations.
or is it tht we need to consider a thin crust pizza wth ABC toppings diff frm a thin crust pizza wth BAC toppgs?
Totally confused
Night reader wrote:8P3 * 3!=8!/(8-3)! *3!=2116 this should be the correct answer in realitysaigopal7 wrote:Pat's pizza offers thick,thin, or deep-dish style crust.There are 8 choices for toppings.
In how many ways can u choose a pizza with three different toppings?
Ans:1008
or call pizzas: thick-x,thin-y, deep-dish-z
x, y or z can be chosen in 8 ways as the first order
x, y or z can be chosen in 7 ways
x, y or z can be chosen in 6 ways
(8*7*6) *3!=2116
