Answer: A) 2893 Explanation: For solving this problem first we would break the whole range in 5 sections 1) From 1 to 9Total number of zero in this range = 0 2) From 10 to 99Total possibilities = 9*1 = 9 ( here 9 is used for the possibilities of a non zero integer) 3) From 100 to 999 - three type of numbers are there in this range a) x00 b) x0x c) xx0 (here x represents a non zero number)Total possibilities for x00 = 9*1*1 = 9, hence total zeros = 9*2 = 18for x0x = 9*1*9 = 81, hence total zeros = 81similarly for xx0 = 81 total zeros in three digit numbers = 18 + 81 +81 = 180 4) From 1000 to 9999 - seven type of numbers are there in this rangea)x000 b)xx00 c)x0x0 d)x00x e)xxx0 f)xx0x g)x0xxTotal possibilities for x000 = 9*1*1*1 = 9, hence total zeros = 9*3 = 27 for xx00 = 9*9*1*1 = 81, hence total zeros = 81*2 = 162 for x0x0 = 9*1*9*1 = 81, hence total zeros = 81*2 = 162for x00x = 9*1*1*9 = 81, hence total zeros = 81*2 = 162 for xxx0 = 9*9*9*1 = 729, hence total zeros = 729*1 = 729for xx0x = 9*9*1*9 = 729, hence total zeros = 729*1 = 729for x0xx = 9*1*9*9 = 729, hence total zeros = 729*1 = 729total zeros in four digit numbers = 27 + 3*162 + 3*729 = 2700thus total zeros will be 0+9+180+2700+4 (last 4 is for 4 zeros of 10000)= 2893

Answer: D) 2679 Explanation: Let x, x+2, x+4, x+6, x+8 and x+10 are six consecutive odd numbers. Given that their average is 52 Then, x + x+2 + x+4 + x+6 + x+8 + x+10 = 52×6 6x + 30 = 312 x = 47 So Product = 47 × 57 = 2679

Answer: A) 2 days Explanation: work done=total number of person x number of days;half of work done = 140 x 66;For half of remaining work 25 extra men are added.Therefore, total men for half work remaining = 140 + 25 = 165;Let 2nd half work will be completed in K days;140 x 66 = 165 x KK = 122;Hence, extra days => 122-120 = 2days.

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: A) Rs. 4000 Explanation: Given ratio of initial investments = 72:43:65 = 105 : 40 : 36.  Let the initial investments be 105x, 40x and 36x.   ∴A:B:C = 105x×4 + 150100×105x×8 : 40x×12 : 36x×12                  = 1680x : 480x : 432x = 35 : 10 : 9.   Hence, B's share = 21600×1054 = Rs. 4000.

Answer: C) 3:49 1/11 Explanation: On straight line means 180 degree angle.180 = 11/2 min – 30 hrs180 = 11/2 m – 30 × 3180 = 11/2 m – 90(180 + 90) 2 = 11 mm = 540/11 = 49 1/11 minutes.