The following question is based on the given data for an examination.

A. Candidates appeared                 10500

B. Passed in all the five subjects     5685

C. Passed in three subjects only     1498

D. Passed in two subjects only       1250

E. Passed in one subject only           835

F. Failed in English only                       78

G. Failed in Maths only                      275

H. Failed in Physics only                    149

I. Failed in Chemistry only                147

J. Failed in Biology only                     221

 

How many candidates passed in at least four subjects ?

We know that, to be in the form that the number of rows and the number of columns to be equal the number should be a perfect square (a2).

Given number is 1200

The perfect number which is above and near to 1200 is 1225 which is 35  35.

Therefore, The minimum number of coins he need is 25. 

Let 'x' be the number of new Rs.2000 notes.

Given for one new 2000 note there are three old 500 notes.

i.e, 3x

Given 10 more new Rs.2000 notes are added to the collection
and the ratio of new Rs.2000 notes to old Rs.500 notes 

x+103x=12⇒x=20

Therefore, number of new Rs.2000 notes =  x+10 = 30.

old Rs.500 notes = 3x = 60.

Thus, the total number of notes in the collection  = 30 + 60 = 90.

Let the total number of workers be x. Then, 

Number of women = x/3 and number of men = x - x/3  = 2x/3

Number of women having children = x/18

Number of men having children = x/3

Number of workers having children = (x/18) + (x/3) = 7x/18

Therefore, workers having no children = x - 7x/18 = 11/18 of all workers.

Clearly, the required number would be such that it leaves a remainder of 1 when divided by 3, 4, 5, or 6 and no remainder when divided by 7. Thus, the number must be of the form (L.C.M of 3, 4, 5, 6) x + 1 i.e., (60x + 1 ) and a multiple of 7. Clearly, for x = 5, the number is a multiple of 7. So the number is 301.

Ayush's present age = 10 years.

His mother's present age = (10 + 20) years = 30 years.

Ayush's father's present age = (30 + 5) years = 35 years.

Ayush's father's age at the time of Ayush's birth = (35 - 10) years = 25 years.

Therefore Ayush's father's age at the time of marriage = (25 - 2) years = 23 years.

Let R, G and B represent the number of balls in red, green and blue boxes respectively.

Then, 

R + G + B = 108 ...(i),

G + R = 2B ...(ii)

B = 2R ...(iii)

From (ii) and (iii), we have G + R = 2x 2R = 4R or G = 3R.

Putting G = 3R and B = 2R in (i), we get:

R + 3R + 2R = 108 =>  6R = 108 => R = 18.

Therefore Number of balls in green box = G = 3R = (3 x 18) = 54.

When Ravi's brother was born, let Ravi's father's age = x years and mother's age = y years.

Then, sister's age = (x - 28) years. So, x - 28 = 4 or x = 32.

Ravi's age = (y - 26) years. Age of Ravi's brother = (y - 26 + 3) years = (y - 23) years.

Now, when Ravi's brother was born, his age = 0 i.e. y - 23 = 0 or y = 23.

Let Varun's age today = x years. 

Then, Varun's age after 1 year = (x + 1) years.

Therefore x + 1 = 2 (x - 12) =>  x + 1 = 2x - 24 =>  x = 25.