This super long ruler measures the heights of people.
If your height reached the mark indicated on the red arrow, how tall would you be in millimetres?
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Super Ruler!
Answer:
Because this ruler measures people’s heights, the numbers are the number of centimetres.
There are 4 spaces between every 10 centimetres on the ruler, so each space is worth:
10 ÷ 2 cm = 2.5 cm
2.5 cm = 25 mm because one centimetre is 10 millimetres.
The person who is the height of the red arrow is 100 cm + one space.
100 cm = 1000 mm
The person is therefore 1000 + 25 = 1025 mm tall.