Very long line
If the line on the right were 0.2mm thick, how long would it need to be to cover an area of one square metre?
Problem
Image
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Student Solutions
Answer: 5 km
0.2 mm
= 0.02 cm
= 0.0002 m
length $\times$ width = area
10 000 $\times$ 0.0002 = 2
5 000 $\times$ 0.0002 = 1