Which of the following is not equal to 1 mm?
a) 100 cm
b) 1/10 cm
c) 1/1000 m
d) 1/1000000 km

Solution:

1 mm means 1 millimeter, where milli stands for 10^-3. We know that 1 km = 10⁶ mm, 1 m = 10³ m, 1 cm = 10 mm

Given options:

a) 100 cm

b) 1/10 cm

c) 1/1000 m

d) 1/1000000 km

Using unit conversion table for length, we see that:

1 mm = 1/10 cm 

Thus, option (A) is not equal to 1 mm

1 cm = 10 mm. Thus, 1 mm = 1/10 cm 

Hence, option (B) is equal to 1 mm

1m = 1000 mm. Thus, 1mm = 1/1000 m

Hence, option (C) is equal to 1 mm

1km = 1000 m = 100000 cm = 1000000 mm. Thus, 1mm = 1/1000000 km

Hence, option (D) is equal to 1 mm

Thus, only option a) i.e. 100 cm is not equivalent to 1mm.

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Which of the following is not equal to 1 mm?

Summary:

Only option a)  i.e. 100 cm is not equivalent to 1 mm.