Answer: B) 2:3 Explanation: Let number of boys = x  , Let number of girls = yTotal numbers of students = x + y(x + y) × 15.8 = 16.4x + 15.4y 0.6x = 0.4yx/y = 0.4/0.6 = 2/3    Ratio of boys and girls in the class is 2:3

Answer: D) Turmoil Explanation: 'Maelstrom' refers to a violent and confused state. The word closest in meaning would be 'turmoil', which also means a state of great disturbance.

Answer: D) 5 minutes Explanation: Let the total capacity of tank be 90 liters.Capacity of tank filled in 1 minute by K = 3 liters.Capacity of tank filled in 1 minute by L = 15 liters.Therefore, capacity of the tank filled by both K and L in 1 minute = 18 liters.Hence, time taken by both the pipes to overflow the tank = 90/18 = 5 minutes.

Answer: B) 30 years Explanation: Let Karan’s present age be x years and Shiva’s present age be y years.Then, according to the first condition,x - 10 = 3(y - 10) or x - 3y = - 20 ..(1) Now, Karan’s age after 10 years = (x + 10) yearsShiva’s age after 10 years = (y + 10)(x + 10) = 2 (y + 10) or x - 2y = 10 ..(2) Solving (1) and (2), we get x = 70 and y = 30Karan’s age = 70 years and Shiva’s age = 30 years.

Answer: B) 20 minutes Explanation: Let the total distance to be covered is 84 kms.Time taken to cover the distance without stoppage = 84/42 hrs = 2 hrsTime taken to cover the distance with stoppage = 84/28 = 3 hrs.Thus, he takes 60 minutes to cover the same distance with stoppage.Therefore, in 1 hour he stops for 20 minutes.

Answer: A) 27 % Explanation: Let the percentage of benzene = X(30 - X)/(X- 25) = 6/4 = 3/2 => 5X = 135  X = 27 So, required percentage of benzene = 27 %

Answer: D) 81.5 Explanation: Let the number of students in classes A, B and C be P, Q and R respectively.Then, total score of A = 83P, total score of B = 76Q, total score of C = 85R.Also given that,(83P + 76Q) / (P + Q) = 79=>4P = 3Q.(76Q + 85R)/(Q + R) = 81=>4R = 5Q,=>Q = 4P/3 and R = 5P/3Therefore, average score of A, B, C = ( 83P + 76Q + 85R ) / (P + Q + R) = 978/12 = 81.5

Answer: C) 7:30 Explanation: Since S.P. = 5 (M.P. - S.P.) => 5 M.P. = 6 S.P.M.P. = (6/5) S.P.Since the percentage discount = Percentage profit,65S.P - S.P65S.P×100 = S.P -C.PC.P×100Therefore, 1/6 = (S.P/C.P) – 1 => S.P = (7/6) C.PM.P = 6/5 S.P = 6/5 x 7/6 C.P = 7/5 C.PTherefore, Ratio of discount to C.P= (M.P – S.P)/C.P = [{(7/5)C.P - (7/6)C.P} / C.P.]= 7/30   Therefore, the ratio is 7 : 30