Divisional MO Higher Secondary 2011 - 30 January 2011 - Blog

» Fri Jan 28, 2011 10:36 pm

Dhaka Divisional Mathematical Olympiad 2011 : Higher Secondary

Question 1:
In a box there are 50 gold rings of 10 different sizes and 75 silver rings of 12 different sizes. The size of a gold ring might be the same as that of a silver ring. What is the minimum number of rings one need to pick up to be sure of having at least two rings different both in size and material?
viewtopic.php?f=41&t=472

Question 2:
A is three digit number all of whose digits are different. B is a three digit number all of whose digits are same. Find the minimum difference between A and B.
viewtopic.php?f=42&t=483

Question 3:
If A=

, A

B=P(A) and A

B=

, find B.

represents empty set.
viewtopic.php?f=42&t=484

Question 4:

a+b+c+d+e= a−b+c+d+e= a+b−c+d+e= a+b+c−d+e= a+b+c+d−e= 1 2 3 4 5

Find a from the above set of equations.
viewtopic.php?f=42&t=485

Question 5:
Find the range of the function

f(x)=

2x

−2

x

2x

−2

x

Here,

x

represents the minimum integer greater than x and

2x

represents the maximum integer less than x.
viewtopic.php?f=41&t=476

Question 6:
One circle is touching another circle internally. The inner circle is also tangent to a diameter of the outer circle which makes an angle of 60

with the common tangent of the circles. Radius of the outer circle is 6, what is the radius of the inner circle?
viewtopic.php?f=42&t=486

Question 7:
In a game Arjun has to throw a bow towards a target and then Karna has to throw a bow toeards the target. One who hits the target first wins. The game continues with Karna trying after Arjun and Arjun trying after Karna until someone wins. The probability of Arjun hitting the target with a single shot is 52 and the probability that Arjun will win the game is the same as that of Karna. What is the probability of Karna hitting the target with a single shot.
viewtopic.php?f=42&t=487

Question 8:
N represents a nine digit number each of whose digits are different and nonzero. The number formed by its leftmost three digits is divisible by 3 and the number formed by its leftmost six digits is divisible by 6. It is found that N can have 2k3l different values. Find the value of k+l.
viewtopic.php?f=42&t=488

Question 9:
Consider a function f:

is so defined that the following relations hold:

f(2n)=f(2n+2) and f

n

X2n

=

n

Xf(2n)

where X is some finite subset of

0

.
Find f(1971) if it is known that f(2011)=1 and f(1952)=−1.
viewtopic.php?f=42&t=489

Question 10:
A point P is chosen inside a right angled triangle ABC, perpendicular lines PS, PQ and PR are drawn from P on AB

BC and AC. PR=1

PQ=2 and PS=3 and

RPS=150

. The length of AB can be written in the form x

y+z where x

y

z are integers. Find x+y+z.
viewtopic.php?f=42&t=490

Problem set (pdf): viewtopic.php?f=8&t=468

LaTeXed by: Zzzz

« January 2011 »
Su	Mo	Tu	We	Th	Fr	Sa
						1
2	3	4	5	6	7	8
9	10	11	12	13	14	15
16	17	18	19	20	21	22
23	24	25	26	27	28	29
30	31

Total comments: 0


Name *:
Email *:

Code *: