jerrys farm produces 2020 watermelons this year with an average weight of 20 pounds. the average weight of watermelons weighing more than 20 pounds is 27 pounds. The average weight of watermelons weighing less than 20 pounds is 18 pounds. At least how many watermelons weigh exactly 20 pounds?
a) 2
b) 4
c) 6
d) 8
e) 10
