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 one year ago
 Students in class are exchanging pencils.
1 student = 0 exchanges
2 students = 2 exchanges
3 students = 6 exchanges
4 students = 12 exchanges
how many exhcanges for 7 sutudents?
*I know the answer to be: 42 exchanges... but how to get it??? I knwo there is a formula, but I dont knwo how is it and how to use it..* help
 one year ago
 Students in class are exchanging pencils. 1 student = 0 exchanges 2 students = 2 exchanges 3 students = 6 exchanges 4 students = 12 exchanges how many exhcanges for 7 sutudents? *I know the answer to be: 42 exchanges... but how to get it??? I knwo there is a formula, but I dont knwo how is it and how to use it..* help

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ParthKohli
 one year ago
Best ResponseYou've already chosen the best response.11 * 0 = 0 2 * 1 = 2 3 * 2 = 6 4 * 3 = 12 5 * 4 = 20 6 * 5 = 30 7 * 6 = 42

raimelgarcia5
 one year ago
Best ResponseYou've already chosen the best response.0yes, thats how i got it... but i know there is a formula... something like an=2n1+(n1) or something like that... (not sure if its that one.... and i know how to use that formula... nor i dont kknow what the formula menas.. :/

Opcode
 one year ago
Best ResponseYou've already chosen the best response.2Okay. Math in the morning ^_^. There's a pattern. 1 student = 0 exchanges 2 students = 2 exchanges 3 students = 6 exchanges 4 students = 12 exchanges S students = X exchanges S students = X exchanges 7 students = 42 exchanges S = Students X = Exchanges The pattern is how many number of students there is minus one from it then times it by that number. So: S  1 = Number to multiple by let's call it (N). S * N = X Let's test it: First say there are 10 students. 10  1 = 9 10 * 9 = 90 Exchanges. Get it?

Opcode
 one year ago
Best ResponseYou've already chosen the best response.2Because. The pattern shows that the number multiplied by the students is always one less than it.

raimelgarcia5
 one year ago
Best ResponseYou've already chosen the best response.0still dont get it.. (sorry for the persistance..) i wanna learn math like for real..

Opcode
 one year ago
Best ResponseYou've already chosen the best response.2So the formula is: (S  1) = N S * N = X S = Students X = Exchanges N = Number to multiple on "S".

Opcode
 one year ago
Best ResponseYou've already chosen the best response.2Say there is: 120 students = ? exchanges Now use the formula: (S  1) = N S = 120 So (120  1) = 119 N = 119 Now for step two: S * N = X We know what S and N are now so plug in the values: 120 * 119 = 14,280 14,280 = X And again: S = Students X = Exchanges N = Number to multiple on "S".

raimelgarcia5
 one year ago
Best ResponseYou've already chosen the best response.0yeah.. i get that... i just didnt know why N = S1 ... but its ok tho... thanks man! :)

raimelgarcia5
 one year ago
Best ResponseYou've already chosen the best response.0u are a really good helper : )

Opcode
 one year ago
Best ResponseYou've already chosen the best response.2So the formula is: (S  1) = N < S is for Students (Given) N is for the Number to multiple on "S". IN the pattern to get N. In this case we minus by "1". Then leading us to: S * N = X S = Students X = Exchanges N = Number to multiple on "S". And no problem ^_^.

ParthKohli
 one year ago
Best ResponseYou've already chosen the best response.1I am waiting to help like Opcode. :(

Opcode
 one year ago
Best ResponseYou've already chosen the best response.2Help me with what O.o? My stuff is just memorizing things like postulates and theorems. Memory with numbers = Head Ache. (For me at lest).
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