Answer: B) 38% Explanation: % Change in Curved Surface Area is given by  %Change in radius + %Change in height + %Change in radius × %Change in height 100   ⇒+20 + 15 + 20×15100 = 38%

Answer: A) 15368 Explanation: The difference between 4632 and 20000 is given by subtracting smaler number from the bigger number. Here the bigger number is 20000 Smaller number is 4632 Now, subtracting 4632 from 20000 20000 - 4632 = 15368 and the resut is an even number.   Hence, The difference between 4632 and 20000 is 15368 and is an even number.

Answer: A) 4 Explanation: Given that,  Number of windows = 50 Each window covering covers 15 windows => 50 windows requires 50/15 window coverings = 50/15 = 3.333   Hence, more than 3 window coverings are required. In the options 4 is more than 3.    Hence, 4 window coverings are required to cover 50 windows of each covering covers 15 windows.

Answer: D) 24 kmph Explanation: Let the speed of the train be 'S' kmph From the given data, Distance = Length of train = D = 200 mts = 200 x 18/5 kms Time = 10 sec given speed of the motorcycler = 12 kmph Relative speed as they are moving in the same direction = (S - 12) kmph (S- 12) = 200 x 18515S - 12 = 48S = 60 kmph  Hence, the speed of the train = S = 60 kmph Now, Let the speed of the jeep be 'x' kmph 60 - x = 200 x 1852060 - x = 36x = 60 - 36x = 24 kmph   Therefore, the speed of the jeep = x = 24 kmph.

Answer: B) 45 yrs Explanation: Let father's age be x year and son's age be y year. According to question, 2(x+y) = 8y _______(I) and (x+y)/2 = 30 => x+y = 60 years__________(II) From equation (I) and (II) 8 y = 120 y = 15 years, Hence x = 45 years.