There are 200 question in a 3 hour examination. Among 200 question, 50 are Mathematics, 100 are from GK and 50 are from Sciences. Ram spent twice as much time on each Mathematics question for each other question. How many minute did he spend on Mathematics questions?

2508 ÷ 15.02 ÷ ? x 11 = 200
? 2508/15 + ? x 11 = 200
? ? = (200 - 167.2) x 1/11 = 2.98 ? 3

Upstream speed of boat = Boat's speed in still water - Rate of stream = 4 - 2 = 2 km/h

Let the requirement odd integers be N, N +2 and N + 4
Then, N + (N + 2) + (N + 4) = 57
? 3N = 51
? N = 17
? The integers are 17, 19, 21.

Because of stoppages, train covers 50 km less per hour.
? Time taken taken to cover 50 km = 50/150 h = (50/150) x 60 = 20 min

Let age of Raman's daughter = N yr
Then, age of Raman's = 3N yr
and age of Raman's mother = (13/9) x 3N = 13N/3 yr
According to the question, N + 3N + 13N/3 = 125
? 3N + 9N + 13N = 125 x 3
? N = (125 x 3)/25 = 15
Hence, required difference = 13N/3 - N = 10N/3
= (10 x 15)/3 = 50 yr

Let boat's rate upstream be U and boat's rate downstream = V

According to the question.
Distance covered in 528 min = Distance covered in 240 min
? Distance covered in 8 h 48 min = Distance covered in 4 h
? U x 8⁴/₅ = V x 4
? (44 x U)/5 = 4V
? V = (11 x U)/5
? Required ratio = (V + U)/2 : (V - U)/2
? = (11U/5 + U)/2 : (11U/5 - U)/ 2
? = 16U/5 : 6U/5 = 8 : 3

Let A's age 10 years ago = x years
Then, B's age 10 years ago = 2x years
? (x + 10) / (2x + 10) = 3 / 4
? 4(x + 10) = 3(2x + 10)
? x(6 - 4) = 40 - 30
? x = 5

&ther4; Total of their present ages = (x + 10) + (2x + 10)
= (3x + 20)
= 35 years

Let B's present age be x years then A's present age be (x + 9) years
As per the given condition
(x + 9 + 10) = 2(x - 10)
? x = 39

? The present age of B = 39 years

75/100 = 0.75