Answer: B) 2 Explanation: Given a2 + b2 = c2   Now  1logc+ab  + 1logc-ab    = logbc+a + logbc-a   = logbc2-a2 = 2logbb = 2

Answer: B) 315 Explanation: Parallelograms are formed when any two pairs of parallel lines (where each pair is not parallel to the other pair) intersect.   Hence, the given problem can be considered as selecting pairs of lines from the given 2 sets of parallel lines.   Therefore, the total number of parallelograms formed = 7C2 x 6C2 = 315

Answer: B) Half year Explanation: 3300 ----- 3% ↑ (1st time interval, 99) → 3399. Here, time interval is given as half-yearly i.e. 6 months.

Answer: B) Rs. 830 Explanation: Let the total amount in the partnership be 'x'.Then A's share = x/3B's share = x/4C's share = x/5D's share = x - (x/3 + x/4 +x/5) = 13x/60 A : B : C : D = x/3 : x/4 : x/5 : 13x/60 = 20 : 15 : 12 : 13 A's share in the profit of Rs. 2490 = 20 (2490/60) = Rs. 830.

Answer: B) 7 hrs Explanation: Given, P can fill in 12 hrs Q can fill in 15 hrs R can fill in 20 hrs => Volume of tank = LCM of 12, 15, 20 = 60 lit => P alone can fill the tank in 60/12 = 5 hrs => Q alone can fill the tank in 60/15 = 4 hrs => R alone can fill the tank in 60/20 = 3 hrs Tank can be filled in the way that (P+Q) + (P+R) + (P+Q) + (P+R) + .... => Tank filled in 2 hrs = (5+4) + (5+3) = 9 + 8 = 17 lit => In 6 hrs = 17 x 6/2 = 51 lit => In 7th hr = 51 + (5+4) = 51 + 9 = 60 lit => So, total tank will be filled in 7 hrs.

Answer: D) -1 Explanation: 3, 7, 6, 5, 9, 3, 12, 1, 15, ... has two different series 1) 3, 6, 9, 12, 15..... 2) 7, 5, 3, 1, ..... -1 is the next number.