Number System
The sum of the ages of a son and father is 65 years. After 5 years the age of father will be double of the age of son. What is the age of son ?
Let the age of the son be x and the age of the father be y.Therefore, x + y = 65 ..........(i)or, 2 x (x + 5) = (y + 5)or, 2x + 10 = y + 5or, 2x - y = 5 ...................(ii)From equations (i) and (ii), x = 20, y = 45
Let the number be 10x + y∴ 3x = 4y ......(1)From (I),x + y = 14 .....(2)Solving equations (1) and (2),x = 8, y = 6∴ Number = 86 From (II)y = 75/100 x x ∴ 3x = 4y.Which is the same as eqn (1)
Since the difference between the divisors and the respective remainders is not constant, back substitution is the convenient method. None of the given numbers is satisfying the condition.
Out of the total six letters, three are vowels (E, I, E) and three are consonants (SRS)Here, E and S come twice If we take all the vowels together the number of letters is 3 + 1 = 4So, letters can be arranged in 41/21 ways and three vowels can be arranged in 31/21 ways ∴ Total number of ways = 41/21 x 31/21= 12 x 3 = 36
EXAMIANS