Answer: B) 29.39 cm Explanation: Volume of water flowing through 1 pipe of diameter x = Volume discharged by 6 pipes of diameter 12 cms.   As speed is same, area of cross sections should be same.    Area of bigger pipe of diameter x = Total area of 6 smaller pipes of diameter 12  i.e πR2 = 6πR12    Here R = R and R1 = 12/2 = 6    ⇒R2 = 6×6×6    R = 14.696    => D = X = 14.696 * 2 = 29.3938 cm.

Answer: C) 209 Explanation: We may have (1 boy and 3 girls)or(2boys and 2 girls)or(3 boys and 1 girl)or(4 boys). Required number of ways = (C16× C34) + C26×C24  + (C36× C14) + (C46)   = (24+90+80+15)  = 209.

Answer: B) 0 Explanation: = log tan10+log tan890 + log tan20+ log tan880+⋯⋯+log tan450     = log [tan10 × tan890] + log [tan20 × tan880 ] +⋯⋯+log1     ∵ tan(90-θ)=cotθ and tan 450=1     = log 1 + log 1 +.....+log 1    = 0.

Answer: B) 14 Explanation: Given Number series is :   3   4   14   48   576   27648   It follows a pattern that,   3   4   4 x 3 = 12   but not 14   12 x 4 = 48   48 x 12 = 576   576 x 48 = 27648       Hence, the odd one in the given Number Series is 14.

Answer: D) 0.375 & 0.1 Explanation: 3/8 as a Decimal : In this we should convert the denominator into 10, 100, 1000, 10000, 100000,... to make it simple. Now to make 8 into 1000, we multiply numerator and denominator with 125 => 3 x 1258 x 125 = 3751000 = 0.375   1/10 as a Decimal : 1 divided into 10 parts of each 0.1.   Therefore, 3/8 = 0.375 and 1/10 = 0.1 in decimals.

Answer: B) 3:2:4 Explanation: Given, y/(x - z) = (y + x)/z = x/yyz = xy + x2 - yz - xz ....(1)Also xy = yx-z ⇒x2 -xz = y2 ....(2)Using (1) and (2), we get yz = xy - yz + y22yz = xy + y22z = x + y Only option (B) satisfies the equation.

Answer: D) 140 mts Explanation: Speeds of two trains = 30 kmph and 58 kmph => Relative speed = 58 - 30 = 28 kmph = 28 x 5/18 m/s = 70/9 m/s Given a man takes time to cross length of faster train = 18 sec   Now, required Length of faster train = speed x time = 70/9  x  18 = 140 mts.