From three different sized animal pictures and their enlargements, students are required to identify the scale factor and the length of an unknown side.
Students estimate a division problem, share their methods, discuss the nice numbers and factors method, and then do more problems using nice numbers and factors.
Students find the number of groups of a given size using division, reverse multiplication, trial and improvement, or iterative equal sharing. Students must show their working.
Task: Students make predictions about evaporation rates of instances where surface areas are a factor, select which variable is being investigated in both examples and explain their answer. Assessment focus: Using knowledge of surface area to make predictions.