Answer: D) 8:3 Explanation: Let the man's rate upstream be x kmph and that downstream be y kmph. Then, distance covered upstream in 8 hrs 48 min = Distance covered downstream in 4 hrs. x x 8 4 = (y x 4) 5 44 x =4y 5  y = 11 x. 5  Required ratio = y + x : y - x 2 2    = 16x x 1 : 6x x 1 5 2 5 2    = 8 : 3 5 5    = 8 : 3.

Answer: B) Platelets Explanation: Blood Platelets are the components of the blood that are helpful in clotting of the blood.

Answer: B) Tomas Walsh Explanation:

Answer: B) -2 Explanation: We know that in A.P series18th term = a + 17d29th term = a + 28dBut given a + 17d = 29..........(i)a + 28d = 18......... (ii)Solving equation (i) and (ii), we getd = -1put d = -1 in any of the above equations and we get, a = 46Now, we know 49th term can be written as, a + 48d putting the value of a and d in the above equation,a + 48d = 46 + 48(-1) = 46 - 48 = -2 Hence, the 49th term is -2.

Answer: B) 7! x 6! Explanation: The students should sit in between two teachers. There are 7 gaps in between teachers when they sit in a roundtable. This can be done in 7P6ways. 7 teachers can sit in (7-1)! ways.    Required no.of ways is = 7P6.6! = 7!.6!

Answer: D) His son Explanation: Since Akhil has no brother or sister, so he is his father's only son.So wife of Akhil's father's son---Akhil's wife.Thus, Akhil's wife is the man's mother or the man is Akhil's son.

Answer: C) Cauvery Explanation:

Answer: C) 2.25 days Explanation: 1 man's 1 day work = 1/108 12 men's 6 day's work = 1/9 x 6 = 2/3 Remaining work = 1 - 2/3 = 1/3 16 men's 1 day work = 1/108 x 16 = 4/274/27 work is done by them in 1 day. 1/3 work is done by them in 27/4 x 1/3 = 9/4 days.