Profit received by Chinna as working partner = 14.5% of Rs. 19600

= 14.5x19600/100 = Rs. 2842

Balance in profit = 19600-2842 = Rs. 16758

Ratio of investment of Chinna & Munna = 80,000 : 1,40,000 = 4 : 7

Hence share of Chinna in investment = 4x16758/100 = Rs. 6093.85

Therefore, Share of Munna = 19600 - 2842 - 6093.85 = Rs. 10664.15

Watson bought the book for Rs. 240 and sold to Johny at a profit of 50%.

S.P = C.P(1 + P%/100)

=> S.P for Watson = C.P for Johny = 240(1 + 50/100) = 240 x 1.5 = Rs. 360

Let Johny quoted the marked price of the book as Rs. M

We know, SP = M.P(1 - Discount(%)/100)

Here discount = 10% to Shekar,

S.P for Johny = M(1 - 10/100) = 0.9M

But Johny want to earn 25% profit,

=> S.P = C.P(1 + P%/100)

=> 0.9M = 360(1 + 25/100)

=> M = (360x1.25)/0.9

=> M = Rs. 500

Therefore, Johny should quote Rs. 500 as the marked price of the book to get 25% profit and allowing 10% discount to Shekar.

Let the amount of juice and water in original mixture '4x' litre and '3x' litre respectively.

According to given data,

4x/3x+6 =8/7

28x=24x+48

28x–24x=48

4x = 48

x = 12

Amount of juice = 4x = 4×12 = 48 litre.

Let marks obtained by N = x

M's marks = 0.80x

L's marks = 1.25 (0.80x)

K's marks = (0.90) (1.25) (0.80x)

= 0.9x

But 0.9x = 360 ⇒ x = 400

Percentage of Marks obtained by N

= 400 x 100/500 = 80%

Here the series follows the pattern that, product of succesive prime numbers i.e,

 2 × 3 = 6

 3 × 5 = 15

 5 × 7 = 35

 7 × 11 = 77

 11 × 13 = 143

 13 × 17 = 221

 17 × 19 = 323

So here in place of 77 the number 63 is written.

So the wrong number is 63.