A family consists of a grandmother, father, mother, and their four sons with their respective wives. Further, each son has a daughter and two sons. How many females are there in all?

Some equations are solved on the basis of a certain system. Find out the correct answer for the unsolved equation on that basis.
If 8 + 8 = 72, 5+5 = 30 and 7+7=56, what is 6+6 =?

A father was twelve times as old as his son twenty years ago. Now he is twice as old as his son. What are the present ages of the son and father?

If “+” denotes ‘ – ‘ , ‘ – ‘ denotes ‘× ‘, ‘×’ denotes ‘÷’  and ‘÷’ denotes ‘+’, then what is the value of
15 – 5 +15 ÷ 45 × 15

Which two signs should be interchanged to make the following equation correct?
5 + 3 x 8 - 12 ÷ 4 = 3 

If ‘÷’ means ‘+’; ‘ –‘ means ‘x’; ‘x’ means ‘÷’ and ‘+’ means ‘ –‘; then 111 – 21 ÷ 7 × 2 + 4 – 127=?

The ratio of the present age of the two brothers is 1: 2. And 5 years ago this ratio was 1: 3. So what will be the ratio of their age after 5 years.

The sum of the ages of a father and his son is 56 years. After 4 years, the father's age will be 3 times his son's age. Their ages are respectively.