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adnanchowdhury
Group Title
How many different numbers can be formed by taking one, two, three and four digits from the digits 1, 2, 7 and 8, if repetition are not allowed?
 2 years ago
 2 years ago
adnanchowdhury Group Title
How many different numbers can be formed by taking one, two, three and four digits from the digits 1, 2, 7 and 8, if repetition are not allowed?
 2 years ago
 2 years ago

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bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
1 digit  4 ways (any one can be chosen)
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
2  digits  4*3 ways (you picked the first one, so now you have 3 to choose from)
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
Waaait, isn't it 4C1
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
I don't understand. Can you list the permutations? I can't seem to understand what the question is saying.
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
Answer is supposed to be 64.
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
For which one?
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
wait im wrong.. hold up. You have to use that formula, like the number of ways of choosing some object from a set of objects with no repetitions
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
ehhh... im lost.. crap i suck at probability
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
Let me call amistre
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
Can you explain what the question is asking? What does it mean when it says: 'take one, two, three and four digits from the digits 1, 2, 7 and 8'?
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
im thinking: Pick one digit from 1,2,7 and 8. Like I can pick 1, or 2, or 7, or 8, so the answer's 4 ways
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
yay amistre's here
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
So would one possibility be 1278?
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
One digit possibilities: 1, 2, 7 and 8. So there are 4 permutations for one digits...?
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
I understand now!
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
4 possibilities for 1 digits. 4x3 = 12 possibilities for 2 digits. And so on..
 2 years ago

bahrom7893 Group TitleBest ResponseYou've already chosen the best response.1
yes that's what i was trying to say adnan
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
Thanks! My problem was in understanding what the question was asking, but after you explained it, i understood.
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.2
1, 2, 7 and 8 1 digit numbers; there are only 4 numbers so: 4 2 digit number: 12 17 18; 4 times = 12; 4P1 * 3P1 = 12 3digit number: 127 128 172 178 182 187; 6*4 = 24; 4*3*2 = 24 4 digit numbers: 1278 1287 1728 1782 1827 1872: 6*4 = 24; 4*3*2*1 = 24 4+12+24+24 = 4+12(3) = 40 i beleive
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.2
lol, almost had that right
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.2
60+4 if i learn to count :)
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
yes lol
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
Any formula i could have used to save me time?
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.2
not really; since it is split up into 4 groups to count individually you still have a bit of work
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.2
knowing the cPr stuff helps tho
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.2
nPr ... cant type
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
I understood the formula before. But now, I just find it confusing.
 2 years ago

amistre64 Group TitleBest ResponseYou've already chosen the best response.2
yeah, its just a "structured" way to count and if you dont use it you tend to go back to the basic method of 1,2,3,4,5s
 2 years ago

adnanchowdhury Group TitleBest ResponseYou've already chosen the best response.0
I see. I work it out intuitively now  probably takes me a bit longer, but i get there eventually.
 2 years ago
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