1.1 Take the unit that the number is rounded to e.g to the nearest 1
1.1.1 Halve it e.g 1/2 = 0.5
220.127.116.11 And take it away/ plus it from the number you are doing e.g 30 - 0.5 = 29.5 (LB) 30+0.5= 30.5 (UB)
2 Calculations with bounds
2.1 e.g.A sack of sand weighs 20 kg measured to the nearest kg. It is used to fill bags that will contain 250 g of
sand measured to the nearest 10 g. Work out the maximum number of bags that can be filled.