Our discussion problems are great for use when you want to develop the reasoning and problem-solving skills in your class. This Year 4 Comparison, Sum and Difference Discussion Problem includes two in-depth questions that help children develop their skills with statistics. Designed for group work and self-correction, we suggest letting your children mark their own work, or that of a partner. To make this easier, we have included an answer page that provides an example answer for each question, though more answers may be possible.