1. 
The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group. What is the average age of the two new students who joined the group?



2. 
If the sum of the interior angles of a regular polygon measures up to 1440 degrees, how many sides does the polygon have?



3. 
How many 3 digit positive integers exist that when divided by 7 leave a remainder of 5?



4. 
If the price of gasoline increases by 25% and Ron intends to spend only 15% more on gasoline, by what % should he reduce the quantity of petrol that he buys?



5. 
The sum of the fourth and twelfth term of an arithmetic progression is 20. What is the sum of the first 15 terms of the arithmetic progression?




