A batsman in his 17th innings makes a score of 85 and their by increasing his average by 3. What is his average after the 17th innings ?

Correct Answer: 69

Explanation:

The total marks of all 5 subjects = 82 x 5 = 410

Total marks of 1st two subjects = 86.5 x 2 = 173

Total marks of last two subjects = 84 x 2 = 168

Now, marks in 3rd subject = 410 - (173 + 168) = 410 - 341 = 69.

Correct Answer: 2:3

Explanation:

Let the number of boys = b

Let the number of girls = g

From the given data,

 

81b + 83g = 81.8(b + g)

81.8b - 81b = 83g - 81.8g

0.8b = 1.2g

b/g = 1.2/0.8 = 12/8 = 3/2

=> g : b = 2 : 3

 

Hence, ratio between the number of girls to the number of boys = 2 : 3.

Correct Answer: 30 kmph

Explanation:

Since equal distances are covered at 40 kmph and 24 kmph, we can apply the formula 2xy/(x+y) Average speed= (2×40×24)/(40+24) = 30 kmph

Correct Answer: 10

Explanation:

Total employees =  25 - 10 × 20 10 = 30

 Hence number of educated employees  = 30-20 = 10

Correct Answer: 3 M^2

Explanation:

We have : ( a + b + c) / 3 = M   or (a + b + c) = 3M.

Now.  a + b + c 2 = 3 M 2 = 9 M 2 .

 

 

 

< = > a 2 + b 2 + c 2 + 2 a b + b c + c a = 9 M 2

 

 

 

a 2 + b 2 + c 2 = 9 M 2 , ( a b + b c + c a = 0 )     

 

 

 

Required mean = a 2 + b 2 + c 2 3 = 9 M 2 3 = 3 M 2 .

Correct Answer: 1.5

Explanation:

Given Five boxes of bananas sell for Rs. 30.

=> 1 Box of Bananas for = 30/5 = Rs. 6

 

Then, for Rs. 9

=> 9/6 = 3/2 = 1.5

 

Hence, for Rs. 9, 1.5 box of bananas can buy.

Correct Answer: 3

Explanation:

Given number of boxes = 14

Number of workers = 4

Now, number of whole boxes per worker = 14/4 = 3.5 

Hence, number of whole boxes per each coworker = 3

Correct Answer: 10,16

Explanation:

Total pice of the two books = Rs. [(12 x 10) - (11.75 x 8)]

 

                                          = Rs. (120 - 94) = Rs. 26.

 

let the price of one book be Rs. x

 

Then, the price of other book = Rs. (x + 60% of x) = Rs.(x+(3/5)x) = Rs. (8/5)x

 

So,  x+(8/5)x =26 <=> x =10

 

The prices of the two books are Rs. 10 and Rs. 16

Correct Answer: 20

Explanation:

Numbers of students in section A = x
? Numbers of students in section B and C = (100 ? x)
? x 70 + (100 ? x) 87.5 = 84 100
=> 70x + 87.5 100 ? 87.5x = 8400
=> 8750 ? 17.5x = 8400
=> 17.5x = 8750 ? 8400 => x = 20.

Correct Answer: 40

Explanation:

The third proportional of two numbers p and q is defined to be that number r such that

p : q = q : r.

 

Here, required third proportional of 10 & 20, and let it be 'a'

=> 10 : 20 = 20 : a

10a = 20 x 20

=> a = 40

 

Hence, third proportional of 10 & 20 is 40.