Reese joined a Pinterest group where members contributed an average of 10 pins per day. The group owner deleted older pins at the rate of 5 pins per week per person. If the group has 20 people and the total number of pins is 1000, how many pins would be there after Reese had been a member for a month?
Thoughts? Step-by-step reasoning:
In a day, the total number of new pins is 10 * 20 = 200. There will be 30 * 200 = 6000 new pins after a month. The total number with old pins present is 6000 + 1000 = 7000 pins. If the owner deletes five pins every week, the total number of deleted pins in a week is 5 * 20 = 100 pins. After a month, the number of deleted pins will be 100 * 4 = 400. The number of pins after the old pins are deleted is 7000 - 400 = 6600 pins.
Thus, the answer is 6600.