Answer: C) Rs.7500 Explanation: p=d×1002R2  Where d is difference, r is rate of interest.  => (48 x 100 x 100) / 8 x 8 = Rs.7500

Answer: A) 4400 Explanation: Let 'P' be the original population at the beginning P x (95/100) x (85/100) = 3553 P = 4400.

Answer: B) 4 : 3 Explanation: Let us name the trains as A and B. Then, (A's speed) : (B's speed) = √b : √a = √16 : √9 = 4:3

Answer: D) 14 min 40 sec. Explanation: Part filled in 4 minutes = 4(1/15 + 1/20) = 7/15   Remaining part = 1 - 7/15 = 8/15   Part filled by B in 1 minute = 1/20   1/20 : 8/15 :: 1 : k   k = (8/15 )x 1 x 20 = 10( 2/3) min = 10 min 40 sec.   The tank will be full in (4 min. + 10 min. 40 sec) = 14 min 40 sec.

Answer: B) 2 : 1 Explanation: Given that train K crosses a pole in 30 seconds and train L crosses the same pole in one minute and 15 seconds. Let the length of train K be Lk and that of train L be Ll given that Lk = 3/4 Ll As the train K and L crosses the pole in 30 seconds and 80 seconds respectively, => Speed of train K = sk = Lk/30 Speed of train L = sl = Ll/80 Lk = 3/4 Ll => sk = 3/4 Ll/(30) = Ll/40 Ratio of their speeds = sk : sl = Ll/40 : Ll/80 => 1/40 : 1/80  =  2 : 1

Answer: B) Rs. 480 Explanation: Let the sum be Rs. P. Then,   P1+252x1002-P= 510   P[982- 1] = 510.   Sum = Rs. 1920   So, S.I. = (1920 x 25 x 2) / (2 x 100) = Rs. 480

Answer: C) 36 sec Explanation: Speed of train relative to man = 67 - 7 = 60 km/hr.= 60 x 5/18 = 50/3 m/sec. Time taken to pass the man = 600 x 3/50 = 36 sec.

Answer: A) 2 lit Explanation: Quantity of fruit juice in the mixture = 70 - [70 x (10/100) ]= 63 litres.   After adding water, juice would form 87.5% of the mixture.   Hence, if quantity of mixture after adding x liters of water, [(87.5) /100 ]*x = 63 => x = 72    Hence 72 - 70 = 2 litres of water must be added.