Answer: A) 3/91 Explanation: In a circle of n different persons, the total number of arrangements possible = (n - 1)!Total number of arrangements = n(S) = (15 – 1)! = 14 !Taking three persons as a unit, total persons = 13 (in 4 units)Therefore no. of ways for these 13 persons to around the circular table = (13 - 1)! = 12!In any given unit, 3 particular person can sit in 3!. Hence total number of ways that any three person can sit =n(E) = 12! X 3!Therefore P (E) = probability of three persons sitting together = n(E) / n(S) = 12! X 3 ! / 14!= 12!x3x2 / 14x13x12! = 6/14x13 = 3/91

Answer: D) 11.5 kgs Explanation: Screws weight = 90x100 = 9000gmsbolts weight = 100 x 150 = 15000gmsweight = screws + bolts => 24000 gms =>24 kgGiven entire box weight = 35.5kgempty box = entire box weight - weight => 35.5kg - 24kg => 11.5kgso the empty box is 11.5kg.

Answer: B) 720 Explanation: Let last digit is 2when second last digit is 4 remaining 4 digits can be filled in 120 ways, similarly second last digit is 6 remained 4 digits can be filled in 120 ways.so for last digit = 2, total numbers=240   Similarly for 4 and 6When last digit = 4, total no. of ways =240and last digit = 6, total no. of ways =240so total of 720 even numbers are possible.

Answer: C) 3:2 Explanation: Let us assume S as number of shirts and T as number of trousersGiven that each trouser cost = Rs.70 and that of shirt = Rs.30Therefore, 70 T + 30 S = 810=> 7T + 3S = 81......(1)T = ( 81 - 3S )/7 We need to find the least value of S which will make (81 - 3S) divisible by 7 to get maximum value of TSimplifying by taking 3 as common factor i.e, 3(27-S) / 7In the above equation least value of S as 6 so that 27- 3S becomes divisible by 7 Hence T = (81-3xS)/7 = (81-3x6)/7 = 63/7 = 9 Hence for S, put T in eq(1), we getS = 81-7(9)/3 = 81-63 / 3 = 18/3 = 6.The ratio of T:S = 9:6 = 3:2.

Answer: B) Rs. 3 Explanation: Let wholesaler dealers marked price = 100%, Retailer's C.P = 80% And the retailer sells at 5% less than the marked price => S.P = 95%If S.P of 95% of the retailer costs Rs.19 to customer,so its C.P of 80% will cost 80 x 19/95 = 16 Profit made by the retailer = 19-16 =  Rs.3

Answer: D) 165 Explanation: Ratio C1:C2 = 3:5 and C2:C3 = 7:11So C1:C2:C3 = 21 : 35 : 55Let the strength of three classes are 21x, 35x and 55x respectively, then Given that 21x + 35x + 55x = 333=> 111x = 333 or x=3So strength of the class with highest number of students =55x = 55x3 = 165.

Answer: C) 66.6 mts Explanation: From above diagramAC represents the hill and DE represents the tower Given that AC = 100 m angleXAD = angleADB = 30° (∵ AX || BD ) angleXAE = angleAEC = 60° (∵ AX || CE) Let DE = h Then, BC = DE = h, AB = (100-h) (∵ AC=100 and BC = h), BD = CE tan 60°=AC/CE => √3 = 100/CE =>CE = 100/√3 ----- (1) tan 30° = AB/BD => 1/√3 = 100−h/BD => BD = 100−h(√3)∵ BD = CE and Substitute the value of CE from equation 1 100/√3 = 100−h(√3) => h = 66.66 mts The height of the tower = 66.66 mts.

Answer: A) 62.5 % Explanation: Let total population = p number of females = 5p/9number of males =(p-5p/9) = 4p/9married females = 30% of 5p/9 = 30x5p/100x9 = p/6married males = p/6unmarried males =(4p/9-p/6) = 5p/18Percentage of unmarried males in the total males = {(5p/18)/4p/9}x100 = (5p/18)x(9/4p) = 125/2 % = 62.5%