Answer: C) 6.66 % Explanation: Let the principle be Rs. PAs the amount double itself the interest is Rs. P tooSo P = P x r x 15/100=> r = 100/15 = 20/3 % = 6.66 %.

Answer: A) 26 min Explanation: Let the required number of minutes = MTotal minutes between 3o'clock and 6o' clock = 180 minutesM + 50 + 4M = 1805M + 50 = 1805M = 130M = 26 minutes.

Answer: D) 8 hrs 15 min Explanation: A can write in 1hour = 32/6 pages Similarly, B in 1 hour = 40/5 pages Together (A+B) in 1 hour = 32/6 + 40/5 = 40/3 So, A+B write 40/3 pages in 1 hour A+B write 110 pages in (3/40) x 110 Hours = 8 hours 15 min.

Answer: B) -2 Explanation: We know that in A.P series18th term = a + 17d29th term = a + 28dBut given a + 17d = 29..........(i)a + 28d = 18......... (ii)Solving equation (i) and (ii), we getd = -1put d = -1 in any of the above equations and we get, a = 46Now, we know 49th term can be written as, a + 48d putting the value of a and d in the above equation,a + 48d = 46 + 48(-1) = 46 - 48 = -2 Hence, the 49th term is -2.

Answer: A) 50 yrs Explanation: Let age of retirement = Sso according to the given condition 25000(x-20)=10000 x 3 + 12000 + 14000 + 16000 + 18000 + 20000 + 22000 + 24000 + 26000 + 28000 + 30000 + 30000(S-33)= 30000 + 210000 + 30000S-990000= 30000S - 750000or 25000S - 500000 = 30000x - 750000or 5000x = 250000or S = 50 yrs.

Answer: C) Rs. 30,000 Explanation: Let first part is 'K' and second part is 'L' then K + L = 50000---------eq1Total profit = profit on x + profit on y7000 = (K x 10 x 1)/100 + (L x 20 x 1)/10070000 = K + 2L-----------------------------------eq270000 = 50000 + Lso L = 20000 then K = 50000 - 20000 = 30000first part on 10% is = Rs.30000

Answer: B) Zymase Explanation:

Answer: C) 54 min Explanation: If virus is K in 1hr i.e 60 minthen in 57 min it was K/2 as it doubles every 3 minutes=> In 54 min it was K/4.At 54 minutes it was K/4.