Question

How much longer is a 12 cm pencil then A 1 dm pen?

Answer 1

20% or 2 cm 1 dm = 10 cm.

Answer 2

1 dm is equal to 10 cm.
To find the answer, you have to convert the dm to cm.
This would be 10 cm, since 1 dm is 10 cm.
The last thing to do is just subtract 10 from 12 to get the answer.
The pencil is 2 cm longer than the pen.