Melody

the reason that your question did not get answered earlier is that you did not specify what 2cm was.

Is it the distance from the centre to the circumference which is called the radius.

Or is it the distance all the way across which is called the diameter.

In his answer Zegroes has assumed it its the diameter.

C = pi * diameter.

C=pi*2

$${\mathtt{2}}{\mathtt{\,\times\,}}{\mathtt{\pi}} = {\mathtt{6.283\: \!185\: \!307\: \!179\: \!586\: \!5}}$$

C=6.28cm correct to 2 decimal places.

I'm impressed Chris.

Great question Takahiro.

I'm going to add that one to our "Puzzles" thread. 

Thanks Takahiro    

Thumbs up from me!

add 3 to both sides and you get

6x-3+3=-51+3

6x = -48

divide both sides by 6 and you get

x=-48/6

x=-8

Good one Chris :-)

6-6--6=6-6+6=6

1% es 28/100

3% es 28/100*3

$${\frac{{\mathtt{28}}}{{\mathtt{100}}}}{\mathtt{\,\times\,}}{\mathtt{3}} = {\frac{{\mathtt{21}}}{{\mathtt{25}}}} = {\mathtt{0.84}}$$

Q=0.84

$${\frac{{\mathtt{3}}}{{\mathtt{16}}}}{\mathtt{\,\times\,}}{\mathtt{32}} = {\mathtt{6}}$$

$${\mathtt{32}}{\mathtt{\,-\,}}{\mathtt{6}} = {\mathtt{26}}$$ students attend

A machine places the top 260 boats in 25 minutes. Do many boats plugged in 2 and ahalf hours?

2 and 1 half hour = 60+60+30 = 150 minutes

260/25*150 = 

$${\frac{{\mathtt{260}}}{{\mathtt{25}}}}{\mathtt{\,\times\,}}{\mathtt{150}} = {\mathtt{1\,560}}$$ 

Because this is a maths forum.

If you want to know about cars you go to a car forum etc etc etc

No I meant that the statement is "A , B and C are all true."

And the statement is clearly false.