A volunteer group wants to make 280 calls. If the calls are distributed evenly to 4 groups of 7 volunteers, how many calls does each volunteer have to make to reach the goal?

Answer 1

There are a total of 4 groups * 7 volunteers per group = <<4*7=28>>28 volunteers.
Therefore each volunteer has to make 280 calls / 28 volunteers = <<280/28=10>>10 calls. Answer: \boxed{10}.