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please help me with the 1st question...

neway pls tell me ur method.may b we can sort it out together and check out...

a car is parked by an owner amongst 25 cars in a row, not at two extremes.on his return, he finds that exactly 15 places are still occupied.the probability that both neighbouring places are vacant is:

a. 15/92

b. 91/276

c. 151/253

ans a.

1. there are 6 diff pairs of gloves.if 8 gloves are selected at random then what is the probability that there are exactly 2 pairs??

2. 12 distinct balls are distributed among 3 different boxes.then what is the probability that first box contains 3 balls?

3. a six-faced die is biased such that it is twice to show an even no. when thrown. if it is thrown thrice then what is the probability that sum of the no. is even?

4.there is a group of 6 persons.they play a game in which each has to select a number from 1 to 4.the group wins if at least 5 of them have same selection of numbers, then what is the probability that the group wins?

5.what is the probability of selecting two squares of 1*1 house from a chess board with one side in common?

yes balganesh..the answer by u isnt correct...

hey u computer001...there is a big difference bw posting the answers and giving the solution...okk...after getting irritated from u i have asked the question again here..

a thin uniform rod of mass m and length l rotates with constant angular velocity omega about the vertical axis passing through the rod's suspension point O. In doing so the rod describes a conical surface with half aperture angle 'theta'.

what is the component of reaction force at O in x direction?

and magnitude of angular momentum of rod about axis of rotation ?

ans;

1. ml

² / 2

2. ml²

/ 12

in a conference of 10 people including A,B,C,D..all have to deliver a speech. what is the probability that A speaks before B and D speaks before C?

ans

1/4

please let me know the method of solving this question

in an examination in an objective test there are two sections containing 10 questions each.In section 1,each objective question has 5 choices and only one choice is correct.Section 2 has 4 choices for each question and more than one choice may be correct.Marks for section 2 is awarded only if a student gives all choices correct.There is no negative marking for any section.For each question in section1 and section 2, 1 and 3 marks are will be awarded respectively.

1. if a student attempts only two questions,one from section 1 and the other from section 2, then what is the probability that he is awarded marks in both questions?

2.what is the probability of getting marks less than 40 for a student ?

3. if a student attempts 4 questions, 2 from each section,then what is the probability that he gets 4 marks ?

4.if a student attempts all the questions then what is the probability that he gets 5 marks in section 1 and 15 in section 2?

answers:

1)1/5 * 1/15

2) 1-{(1/5)^10}*{(1/15)^10}

3)(1/5)*(1/15)*(14/15)*(4/5)*4

4)10C5*(1/5)^5*(4/5)^5*10C5*(1/15)^5*(14/15)^5

yes c=1/2, a= -3/2 and b can take all real values...similar question was askd in JEE(mains) long back........

WHAT DO U MEAN BY THE STATEMENT

7² = 5 mod(11)

there is a point in posting the answers...

the one who is asking doesnt know the way..at least give me hints...so please try posting the hints..or do one thing...click a picture of ur solutions and post it..or mail them to me...

fine fine...was unable to understand the term telescopic sum..

sandeepramesh cudnt understand the final step..pls explain in detail..

if (a-b)² + (b-c)²+(c-a)² = (a + b - 2c)²+ (a + c - 2b)²+ (c+ b - 2a)² with a,b,c real and non zero then if a/b = k, what will b/c be?

1. 2k

2. k + k²

3. k² - k

4. 1