Division is about creating equal groups from a number. You can use division to find out how many groups will be created and how many will be in each group. Creating equal groups means each group has ...

Command sentences tell somebody to do something. Bring me the ball. They usually start with an imperative verb, sometimes called a ‘bossy verb’ because it tells someone what to do. These might be ...

Correspondence to Maria Quigley, National Perinatal Epidemiology Unit, University of Oxford, Old Road Campus, Headington, Oxford OX3 7LF, UK; maria.quigley{at}npeu.ox.ac.uk Objective To investigate ...