How do some moves work against dual types?

Question

Let's say I have a Pokemon that is a dual type, and one type is resistant to a move, but the other type is weak to that move. Will the move be super effective, normal, or not very effenctive?

Example:
I have an Empoleon.
Magby used Flamthrower!
Since Empoleon is Water-Steel, will the Flamethrower will Super Effective, Normal Effectiveness, or Not very Effective?

Answer 1

It will be Normal effective. Water resists Fire, but Steel doesn't so they just cancel each other out, so it's Normal Effective

Source- personal experience

Answer 2

It will be normal.
Since it is super effective against steel, and resisted by water, they cancel each other out, making it neutral.

Answer 3

http://pokemondb.net/type/dual

According to this chart is is neutral.

Dual types work in a pretty basic way.

• If Chimchar used Flamethrower on Abomasnow, it would be 4x because Ice is weak to fire, as well as grass.

• If a steel type attacked a Fire / Electric type, it would do 1/4 damage because Fire and Electric resist steel.