1 . | Answer : Option C | Explanation : | Let the present age of A and B be ‘x’ and ‘y’ respectively. x + y = 70... (i) From (I), (y – 5) = 2(x –5) or 2x – y = 5 ... (ii) From eqn (i) and (ii), x = 25 and y = 45 From (ii), (x + 5) =$60\over100$(y+5) or, 5x – 3y = – 10 ... (iii) From eqn (i) and (iii), x = 25, y = 45 | | | 2 . | Answer : Option D | Explanation : | Let the number be 10x + y. From (II), y > x and from (I), y – x = 3 but to find the value of ‘x’ and ‘y’ we need one more equation | | | 3 . | Answer : Option D | Explanation : | From (I), X = $62.5\over100$x Z or X < Z ... (1) From (II), X – Y = 30 or X > Y ... (2) From (1) and (2), Z > X > Y ‘Z’ is the greatest. | | | 4 . | Answer : Option D | Explanation : | From (II), 12 < X < 14 ‘X’ can be 13 And 10 < Y < 14, so ‘Y’ can be 11, 12, 13 From (I) X > Y Y = 11 or 12 when Y = 11 then X + Y = 13 + 11 = 24 (even number). But when Y = 12 then X + Y = 13 + 12 = 25, which is an odd number. So, data given is not sufficient.
| | | 5 . | Answer : Option D | Explanation : | Let the speed of the boat in still water be ‘x’ and the speed of the stream be ‘y’. Speed downstream = x + y And speed upstream = x – y From (I), distance = 3x(x + y) And from (II), distance = 5(x – y) 3(x + y) = 5(x – y) 3x + 3y = 5x – 5y 2x = 8y $x\over y$=$4\over1$ x : y = 4 : 1
| | | 6 . | Answer : Option D | Explanation : | | | | 7 . | Answer : Option A | Explanation : | Reqd%=$63\over300$x100=21% | | | 8 . | Answer : Option D | Explanation : | Total students who passed in Physics = 45 + 50 + 40 + 72 = 207 | | | 9 . | Answer : Option C | Explanation : | Ratio =$72+63\over50$=$135\over50$=$27\over10$=27:10 | | | 10 . | Answer : Option D | Explanation : | Students who passed at most in one subject = 45 + 50 + 30 + 63 = 188 | | | |

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