## Search found 81 matches

Tue Jan 08, 2019 1:04 pm
Forum: National Math Olympiad (BdMO)
Topic: BDMO National Junior 2018/3
Replies: 1
Views: 970

### BDMO National Junior 2018/3

Shoumo, Oindry and Esha take turns counting from $1$ to one more than the last number said by the last person. Shoumo starts by saying “$1$”, so Oindry follows by saying “$1,2$”, Esha follows by saying “$1,2,3$”. Shoumo then says “$1,2,3,4$”, and so on. What is the $50^{th}$ number said ? (For examp...
Tue Jan 08, 2019 1:00 pm
Forum: National Math Olympiad (BdMO)
Topic: BDMO National Junior 2018/2
Replies: 1
Views: 976

### BDMO National Junior 2018/2

If the average of first $n$ positive integers is $2018$, then find the value of n ?
Tue Jan 08, 2019 12:57 pm
Forum: National Math Olympiad (BdMO)
Topic: BDMO National Junior 2018/1
Replies: 1
Views: 940

### BDMO National Junior 2018/1

The area of a rectangle is $240$. All the lengths of the sides of this rectangle are integer, what can be the lowest possible perimeter of this rectangle?
Tue Jan 08, 2019 12:22 pm
Forum: National Math Olympiad (BdMO)
Topic: BDMO National Secondary 2018/7
Replies: 2
Views: 1516

### BDMO National Secondary 2018/7

The vertices of a regular nonagon ($9$-sided polygon) are labeled with the digits $1$ through $9$ in such away that the sum of the numbers on every three consecutive vertices is a multiple of 3. Two acceptable arrangements are considered to be indistinguishable if one can be obtained from the other ...
Tue Jan 08, 2019 12:15 pm
Forum: National Math Olympiad (BdMO)
Topic: BDMO National Secondary/Higher Secondary 2018/5
Replies: 5
Views: 2788

### BDMO National Secondary/Higher Secondary 2018/5

Four circles are drawn with the sides of quadrilateral $ABCD$ as diameters. The two circles passing through $A$ meet again at $A′$ . The two circles passing through $B$ meet again at $B′$ . The two circles passing through $C$ meet again at $C′$. The two circles passing through D meet again at $D′$. ...
Mon Feb 19, 2018 8:25 pm
Forum: National Math Olympiad (BdMO)
Topic: BDMO 2017 National round Secondary 5
Replies: 15
Views: 5952

### Re: BDMO 2017 National round Secondary 5

ninadgns wrote:
Mon Feb 05, 2018 8:53 pm

how aq=bq=r/2?
No problem at all. First read carefully.
nahin munkar wrote:
Wed Feb 15, 2017 12:27 am
A synthetic solution :

We denote the inscribed circle as $\omega$ , & $P,Q$ be the tangent point of arc $BC$ & (line) $AB$ resp with $\omega$.
SO, $AB=r$ &
$AQ=BQ= \dfrac{r}{2}$
(as 'Q' is the midpoint of AB)
Sat Apr 15, 2017 6:53 pm
Forum: Social Lounge
Topic: BDMO Forum Mafia #2
Replies: 30
Views: 28494

### Re: BDMO Forum Mafia #2

1. ahmedittihad
2. Raiyan Jamil
3. dshasan
4. Epshita32
5. Ananya Promi
6. TashkiManda
7. nahinmunkar
Tue Apr 04, 2017 6:41 pm
Forum: Social Lounge
Topic: BDMO Forum Mafia #1
Replies: 52
Views: 25379

### Re: BDMO Forum Mafia #1

As I said before, I suspect $ds$-$rj$ as mafias. $ds$ seems more suspicious. So, I'm gonna vote him.

VOTE: (dshasan)
Mon Apr 03, 2017 8:25 am
Forum: Social Lounge
Topic: BDMO Forum Mafia #1
Replies: 52
Views: 25379

### Re: BDMO Forum Mafia #1

Oka. In brief of recent posts, it seems, $hasan$-$jamil$ company may be mafia. But, we have more information about ds more than rj & any other.He is also suspecious too at everyone's point of view. So, should we vote him ?
Mon Apr 03, 2017 12:55 am
Forum: Social Lounge
Topic: BDMO Forum Mafia #1
Replies: 52
Views: 25379

### Re: BDMO Forum Mafia #1

First of all, There is no logic against me as a mafia 8-) . But I'd like to point out some logic . 1.My first suspicion is $dshasan$, who may kill rahul bro first, he also voted & convinced against two vanilla townies as epshita32 said so. 2.My 2nd suspicion is $raiyan$ $jamil$. His nature ,we know,...