Question 1101208
A tonne is 2000 kg.
The key is that the number of bags is equal for all sizes
a)
2x+3x=2000
5x=2000
x=2000/5=400 
800 kg of 2 kg bags and 1200 kgs of 3 kg bags (400 bags of each size) 
b)
2x+ 3x +5x=2000
10x=2000
x=200
2x=400 kgs of 2 kg bags (200 bags of each size) 
c)
2+3+5+10 =20
2000/20=100 bags of each size