Mathematics quiz on Profit, loss and Ages (14-12-2020)

In order to get a gain of 20%, a buyer will sell the remaining orange at which rate(Rs./dozen), if he purchased 450 oranges at the rate of Rs 20 per dozen and 30 oranges were rotten among them.

A person purchased a cooler for Rs 9,550. He spends Rs 200 on transportation and made a stand in Rs 500. Still he disliked it and sold the complete set in Rs 9,500. Find the percentage profit or loss of the person?

If a person loses 30 % on selling price, then what percentage of loss will be made on the cost price?

By selling 138 items Sanjay suffered a loss equal to the selling price of 12 items. His loss per cent is:

If 4 years ago the ratio between the ages of Ram and Rakesh was 5 : 6 and the sum of their ages at present is 52 years, what is the ratio of their present ages?

The ratio of ages of two family member is 6 : 11 and the age of one of them is greater than the other by 35 years. The sum of their ages in year is:

Ten years before, the ratio of ages of P and Q was 15:11. After 11 years from now, the ratio of their ages will be 9:8. What is the present age of Q?

Himanshu's brother is 4 years elder to him. His mother was 28 years of age when he was born, while his father was 30 years of age when his sister was born. If his sister was 5 years of age when his brother was born, what were the respective age of Himanshu's mother and father when his brother was born?

Find the age of teacher, if the average age of 25 students is 13 years and if the age of their teacher is included, it becomes 14 years.