Answer: B) 3/10 Explanation: Here, S = {1, 2, 3, 4, ...., 19, 20}=> n(s) = 20Let E = event of getting a multiple of 4 or 15 =multiples od 4 are {4, 8, 12, 16, 20}And multiples of 15 means multiples of 3 and 5= {3, 6 , 9, 12, 15, 18, 5, 10, 15, 20}.= the common multiple is only (15).=> E = n(E)= 6Required Probability = P(E) = n(E)/n(S) = 6/20 = 3/10.

Answer: D) 7.5 hrs Explanation: Ratio of times taken by A and B = 160 : 100A can do the work in 12 daysLet B can do the work in "D" days=> 160:100 = 12 : D=> D = 12 x 100/160 = 7.5 hrs

Answer: B) 45 Explanation: Let number of 20 ps coins = x and number of 25 ps coins = y Given total coins in the bag = 50 x + y = 50.......(1) But the total money in the bag = Rs. 10.25 0.20x + 0.25y = 10.25 20x + 25y = 1025.........(2) Now multiplying (1) by 25 we get 25x+25y=1250.............(3) By solving (2) and (3) 20x + 25y = 1025; => x = 45; Then, the no. of 20 ps coins are 45.

Answer: D) All the above Explanation: A greenhouse gas (GHG) is any gas in the atmosphere that absorbs and emits radiation in the thermal infrared range.   The increase in average global temperatures that results from an enhanced greenhouse effect. Effects of increased greenhouse gas emissions: Increases in the different greenhouse gases have other effects apart from global warming including ocean acidification, smog pollution, ozone depletion as well as changes to plant growth and nutrition levels.

Answer: D) 1/7 Explanation: Multiplicative inverse is nothing but a reciprocal of a number.  It is defined as one of a pair of numbers that when multiplied with another number equals the number 1. Multiplicative inverse or reciprocal of 7 is  7 x n = 1 => n = 1/7.   Hence, Multiplicative inverse or reciprocal of 7 is  1/7.

Answer: D) 1022 Explanation: Lowest 4-digit number is 1000.LCM of 3, 4 and 5 is 60.Dividing 1000 by 60, we get the remainder 40. Thus, the lowest 4-digit number that exactly divisible by 3, 4 and 5 is 1000 + (60 - 40) = 1020.Now, add the remainder 2 that's required. Thus, the answer is 1022.

Answer: D) 60 kms Explanation: Let the distance be d.  d8-2-d8+2 = 4   => 2d = 120    => d = 60 kms.

Answer: C) 462 Explanation: Assume that the number is taken as XYZ.Condition 1 => Z = sq.root(x) => Possible digits of X is 1,4,9Condition 2 => Y = X + ZX Y Z1 2 14 6 29 12 3 => (wrong because it is 4 digit.) and 121 is not divisible by 2 The answer is 462.