The sum of the digits of a two digit number is 9. On adding 27 to the number , its digits are reversed. The number is

1. 36
2. 45
3. 54
4. 72

The ages of A and B are in the ratio 2 : 5. After 6 years, their ages will be in the ratio 1 : 2. The present age of B is

1. 20 years
2. 24 years
3. 30 years
4. 36 years

Fill in the blanks :

(i) An equation involving one variable with highest power ……………, is called a linear equation in that variable.

(ii) The solution of an equation is also called …………… of the given equation.

(iii) The process in which we drop a term from one side of an equation and put it on the other side with sign changed is called …………… .

(iv) A linear equation can have at the most …………… solution(s).

(v) If thrice a number increased by 8 gives 23, then the number is …………… .

(vi) If x - 7 = 4, then 3x - 15 is equal to …………… .