39126

50 children=£42.50
47 pensioners=£47.00
3 adults=£10.50
£42.50=50x0.85p
47x£1.00
£3.50x3
100 seats are taken...........50 children+47pensioners+3adults=100
It all adds up to £100.00
£42.50+£47.00+£10.50=£100.00