Let a girl's share = x + 20
4x + 5(x + 20) = 18,100
4x + 5x + 100 = 18,100
9x + 100 = 18,100
9x = 18,000
x = 18,0009
x = 2,000
∴ Each boy gets N(2,000 + 20)
= N2,020.