If -4$1 = 4, 7$-7 = 49 and 3$1 = -3, then find the value of -8$-5 = ?

If “*” denotes “added to”, “&” denotes “divided by”, “@” denotes “multiplied by” and “%” denotes “subtracted from”, then
399 & 19 @ 21 % 41 * 100 =?

The total age of a mother and her son is 60 years. The difference between their ages is 30 years. Find out the age of the mother.

There were 15 persons in a group, they shook hands with each other, then tell how many times the total number of hands were shaken -

The ratio of present ages of Suresh and Manish are 5 : 1 respectively. After how many years the ratio of the ages of Suresh and Manish will become 3 : 1 if the present age of Manish is 7 years -

Damini is twice as old as Hari. Hari is 5 years older than Nipa. In 5 years, Damini will be three times as old as Nipa. How old is Hari now?

Study the following information carefully and answer the questions given below:
There are six persons of different weights. Three persons are heavier than Rohan. Two person’s weight is in between Sohan and Geeta. Rajesh is heavier than Rakesh but lighter than Ram. Neither Rakesh nor Geeta is lightest person. Weight of 2nd heaviest person is 66kg. Weight of all persons are in whole numbers. What is the weight of Sohan?

When Rahul was born, his father was 32 years older than his brother and his mother was 25 years older than his sister. If Rahul's brother is 6 years older than him and his mother is 3 years younger than his father, how old was Rahul's sister when he was born ?