29) Simplification of (xm+3n .x4m-9n ) / x6m-6n (a) xm (b) x -m (c) xn (d) x-n
30) The ages of two persons are inthe ratio 5:7 . Eighteen years ago their ages were in the ratio of 8:13, their present ages (in years) are : (a) 50, 70 (b) 70, 50 (c) 40, 56 (d) None
31) If 4x = 5y = 20z then z is equal to : (a) xy (b) (x+y) / xy (c) 1/xy (d) xy/ (x +y)
32) log4 (x2 +x) – log4 (x +1) = 2 Find x : (a) 16 (b) 0 (c) -1 (d) None of these