A company produces an average of 4000 items per month for the first 3 months. How much items, it must produce on an average per month over the next 9 months to get average of 4375 items per month over the whole year? 

In a class of 66 students there are 33 girls. The average weight of these girls is 61 Kg and average weight of the full class is 66 kgs. What is the average weight of the boys of the class?

Eight consecutive numbers are given. If the average of the two numbers that appear in the middle is 6, then the sum of the eight given numbers is: 

Mrs. Reena’s family has 10 males and a few women, the average monthly consumption of Wheat per head is 8 kg. If the average monthly consumption of Wheat per head be 10 kg in the case of males and 6 kg in the case of women, find the number of women in Reena’s family?

The average weight of P, Q and R is 93 kg. If the average weight of P and Q is 89 kg and that of Q and R average weight is 96.5 kg ,  then the weight (in kg) of Q is____.

The owner of a bike buys petrol for 3 years continuously at Rs 64, Rs 80 and Rs 320 per litre respectively. If he spends Rs 32,000 every year buying petrol, what is the average price per litre of petrol?