Answer: A) 48 Explanation: 3X + 4y = 240by substitute through options 48 is correct

Answer: D) 30 min Explanation: Part filled by (A + B) in 1 minute = (1/60 + 1/40) = 1/24Suppose the tank is filled in x minutes.Then, x/2(1/24 + 1/40) = 1(x/2) * (1/15) = 1 => x = 30 min.

Answer: D) Grand-mother Explanation: My father's brother's only sibling is my father. My father's mother is my grandmother. My sister's only brother is myself. So she is my Grandmother.

Answer: A) 3/91 Explanation: In a circle of n different persons, the total number of arrangements possible = (n - 1)!Total number of arrangements = n(S) = (15 – 1)! = 14 !Taking three persons as a unit, total persons = 13 (in 4 units)Therefore no. of ways for these 13 persons to around the circular table = (13 - 1)! = 12!In any given unit, 3 particular person can sit in 3!. Hence total number of ways that any three person can sit =n(E) = 12! X 3!Therefore P (E) = probability of three persons sitting together = n(E) / n(S) = 12! X 3 ! / 14!= 12!x3x2 / 14x13x12! = 6/14x13 = 3/91

Answer: C) 10 years Explanation: Let the age of the daughter today be ‘x’ years. Mother’s age today = 3x years After 10 years, we have 3x + 10 = 2(x + 10) x = 10 years.

Answer: C) 3.5 Explanation: Let the number is = x (89)2 + x2 = 16202 x2 = 8281 x = 91 => (1/26) of 91 = 3.5

Answer: B) 13 + 1/3 days Explanation: C alone can finish the work in 40 days.As given C does half as much work as A and B together => (A + B) can do it in 20 days(A + B)s 1 days wok = 1/20.A's 1 days work : B's 1 days Work = 1/2 : 1 = 1:2(given)A's 1 day’s work = (1/20) x (1/3) = (1/60) [Divide 1/20 in the raio 1:2]B's 1 days work = (1/20) x (2/3) = 1/30(A+B+C)'s 1 day's work = (1/60) + (1/30) + (1/40) = 9/120 = 3/40 All the three together will finish it in 40/3 = 13 and 1/3 days.

Answer: C) 4 Explanation: Let the number of boys in the group originally be x.Total weight of the boys = 30xAfter the boy weighing 35 kg joins the group, total weight of boys = 30x + 35So 30x + 35 + 31(x + 1) = > x = 4.