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Maths Puzzle
Q. Find the number of 4 digit numbers that are formed by using digits 1,2,5,6,7 so that that four digit numbers divisible by 3.
Read Solution (Total 3)
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- 24
If digits are used only once,Out of the given digits, number formed with 1,2,5,7 will be divisible by 3
Total 4 digit numbers formed=4!=24 - 10 years agoHelpfull: Yes(3) No(0)
- I think its 4!
because we can use only 1,2,5,7 to be divided by 3. - 10 years agoHelpfull: Yes(0) No(0)
- any num can be div by 3
iff its digits sum is div by 3
so we can consider 1 2 5 7 to make it.(sum=15)
we can arrange 1257 in 4! ways (bcoz unique digits)
so ans is 24 - 10 years agoHelpfull: Yes(0) No(0)
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