Answer: B) 13 years Explanation: Given R + S + M + D = 76 => R+7 : S+7 : M+7 : D+7 = 7:6:5:8 => Let the ratio = x => M+7 = 5x => M = 5x-7 => R = 7x-7 => S = 6x-7 => D = 8x-7 => R + S + M + D = 76 => 7x-7 + 6x-7 + 5x-7 + 8x-7 = 76 => 26x - 28 = 76 => 26x = 104 => x = 4 => Mahesh's present age = 5x-7 = 20 - 7 = 13 years.

Answer: A) Astronomy Explanation: Astronomy is the study of planets and heavenly bodies. Historically, astronomy has focused on observations of heavenly bodies. It is a close cousin to astrophysics. Succinctly put, astrophysics involves the study of the physics of astronomy and concentrates on the behavior, properties and motion of objects out there.

Answer: D) 9, 27, 21 Explanation: Let Anushka age = XCharu latha 12 yrs older than Anushka so Charu latha age = x+12Kajal is thrice as old as Anushka so Kajal age = 3xThe ages of Anushka, Kajal and Charu latha together are 57 yearsi.e x + (x+12) + 3x = 57=> 5x = 45:- x = 9Anushka age = 9Kajal age = 3x = 27Charu latha age = x+12 = 21

Answer: B) Accoustics Explanation: Accoustics is a subject deals with the Study of sound   Aesthetics is a Philosophy of fine arts   The science or art of flight is called Aeronautics   The science of soil management is called Agronomy.

Answer: D) Screen Explanation: A touch screen is the only device which works as both an input and an output device among the given options. You view the options available to you on the screen (output) and you then use your finger to touch the option that you have chosen (input).   Hence, Screen is not purely output device.

Answer: A) 600 Explanation: Two men, three women and one child can be selected in ⁴C₂ x ⁶C₃ x ⁵C₁ ways = 600 ways.

Answer: A) 22/7 x 24/35 Explanation: Since level of water increased in cylinder by height 4.  This is because of the rectangular block .   Therefore , area of rectangular block immersed in water is  = 227×6×6×4   Thats why portion of block immersed in water is  = (22/7 * 36 * 4) / total vol. of rectangle  = (22/7 * 36 * 4)/ (7*5*6)  = (22/7 * 24)/ 35.

Answer: A) 12 years Explanation: Given the average age of couple and their son = 40 => Sum of age (H +W +S) = 40×3 Let the age of daughter in law at the time of marriage = D years Now after 10 years, (H + S +W) + 3×12 + D +12 + 10 = 38×5 178 + D = 190 D = 190 -178 = 12 years