There are three children aged 3, 4 and 5 years in a room. If another 4 year old child enters the room what will be the effect on mean age and variance age?

Read and fill in the gaps ( a) Present age of Mukti is x years, 4 years later her age will be ― years.

The sum of the present ages of a mother and her daughter is 55 years. After 16 years, the age of the mother will be double the age of her daughter . What will be the sum of the ages of the mother and her daughter after 5 years from the present ?

There are three persons aged 50, 60, and 70 years. The probability to live 10 years more is 0.8 for a 50 years old, 0.5 for as 60 years old and 0.2 for a 70 years old person. Find the probability that at least two of the three persons will remain alive 10 years hence.

Express the following statements in the form of simultaneous linear equations and solve them by drawing graphs : (ii) At present the age of a father is 28 years more than that of his son. After 10 years the age of father will be 3 times of the age of his son. Find the present ages of both father and son.

I am 4 years younger than my brother. If brother's age is X years, my age in terms of my brother's age.

sum of the ages of a father and his son is 55 years. After 10 years , the father's age will be double of that of his son. What are their present ages ?

The expenditure of covering the four walls with papers at the rate of 70 paise per sq-metre is ₹ 157.50 . If the height of the room be 5 metres and the ratio of the length and breadth of the room be 4 : 1, then what will be the length and breadth of the room ?

The age of the father is 4 times to that of his son, 8 years hence the sum of their ages will be 71 years what was the age of the father when the son was born ?