Dhaka Higher Secondary 2010/4
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Please don't post problems (by starting a topic) in the "Higher Secondary: Solved" forum. This forum is only for showcasing the problems for the convenience of the users. You can post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
Please don't post problems (by starting a topic) in the "Higher Secondary: Solved" forum. This forum is only for showcasing the problems for the convenience of the users. You can post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
From $1$ to $1000$, how many integers are multiples of $3$ or $6$ but not of $5$?
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leonardo shawon
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- Joined:Sat Jan 01, 2011 4:59 pm
- Location:Dhaka
Re: Dhaka Higher Secondary 2010/4
if u say 3 or 6 then the answer is 133.
as 6 is divided by 3, so the common multiple between 6 and 5 will be cancelled. They r 33 numbers who are divided by both 5 and 6. And there are 166 numbers who are divided by both 3 and 6. So the answer is 166-33=133
as 6 is divided by 3, so the common multiple between 6 and 5 will be cancelled. They r 33 numbers who are divided by both 5 and 6. And there are 166 numbers who are divided by both 3 and 6. So the answer is 166-33=133
Ibtehaz Shawon
BRAC University.
long way to go .....
BRAC University.
long way to go .....
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leonardo shawon
- Posts:169
- Joined:Sat Jan 01, 2011 4:59 pm
- Location:Dhaka
Re: Dhaka Higher Secondary 2010/4
but if u say either 3 or 6 then the answer is 267.
There are 333 numbers who are multiple of either 6 or 3. And 66 numbers are common between them. So the rest is answer
There are 333 numbers who are multiple of either 6 or 3. And 66 numbers are common between them. So the rest is answer
Ibtehaz Shawon
BRAC University.
long way to go .....
BRAC University.
long way to go .....