In a group of 1000 people the number of people who drink tea is 400 the number of people who drink coffee 500 the number of people who drink ice -tea 300 and the number of people in the group holicks is 200 .The number of people in the group who drink all the four beverage is 40 number of people who drink exactly two beverage is 120 the number of people who drink exactly three beverage is 90. what is the number of people in the group who do not drink any beverage at all