Answer: B) 6 kmph Explanation: Speed of the stream = 1Motor boat speed in still water be = x kmphDown Stream = x + 1 kmphUp Stream = x - 1 kmph[35/(x + 1)] + [35/(x - 1)] = 12x = 6 kmph

Answer: C) 2/21 Explanation: Given that there are three blue marbles, four red marbles, six green marbles and two yellow marbles.   Probability that both marbles are blue = ³C₂/¹⁵C₂ = (3 x 2)/(15 x 14) = 1/35 Probability that both are yellow = ²C₂/¹⁵C₂ = (2 x 1)/(15 x 14) = 1/105 Probability that one blue and other is yellow = (³C₁ x ²C₁)/¹⁵C₂ = (2 x 3 x 2)/(15 x 14) = 2/35   Required probability = 1/35 + 1/105 + 2/35 = 3/35 + 1/105 = 1/35(3 + 1/3) = 10/(3 x 35) = 2/21

Answer: B) 26.166 minutes Explanation: Upto first 5 minutes I, J and K will fill => 5[(1/20)+(1/30)+(1/40)] = 65/120 For next 6 minutes, J and K will fill => 6[(1/30)+(1/40)] = 42/120 So tank filled upto first 11 minutes = (65/120) + (42/120) = 107/120 So remaining tank = 13/120 Now at the moment filling with C and leakage @ 1/60 per minute= (1/40) - (1/70) = 3/280.So time taken to fill remaining 13/120 tank =(13/120) /(3/280) = 91/6 minutes   Hence total time taken to completely fill the tank = 5 + 6 + 91/6 = 26.16 minutes.

Answer: C) Rs. 4511 Explanation: Now as per question, Karan invested for 12 months and Satish invested for 7 months. So, Karan:Satish = (29000 x 12):(18000 x 7) = 348:126 = 58:21   Satish Ratio in profit will be= 16970×2179 = Rs. 4511

Answer: C) Parrot Explanation: All except Parrot are birds of prey.

Answer: B) 17 Explanation: Total student= 39, boys : girls = 2:1, hence no of boys= 2/3(39)= 26num of girls= 1/3(39) = 13 , since radhika ranked 15 among 39 student from topand ranked 8 among girls from bottom , this means 7 girls are below radhika, rest 13-9= 5 girls are above her, now from 14 toper 5 are girls hence 14-5=9 boys.Hence num of boys below radhika are 26-9=17