Which of the following is NOT an example of an exact number? The hexagon has 6 sides.
There are 3 wheels on a tricycle.
The desk is 84 cm long.
The table has 4 legs.

the desk is 84 cm long

Explanation:

A hexagon always have 6 sides.

A tricycle always have 3 wheels. That's why it's called tri

A tables Always have 4 legs. Well in most cases.

But a desk is not always 84 cm

The desk is 84 cm long

Explanation:

Exact numbers are either defined numbers or the result of a count

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