Planning the setting out of a brick wall, calculating the number of bricks needed and working with different sized bricks.
Mixing concrete using a ratio, setting the concrete and measuring the slump with a ruler to check consistency of the concrete mix.
Planning out how many patio slabs are needed to complete the job using a diagram showing the area of the patio space.
Checking a time sheet for hours worked, calculating the pay for the week and converting times to decimal numbers.
Measuring out where roof trusses will go, calculating the number of roof trusses needed and marking out the trusses equally using a ruler.