Melody

A nice answer Titanium :)

$${\mathtt{3.5}}{\mathtt{\,\times\,}}{\mathtt{13.85}} = {\frac{{\mathtt{1\,939}}}{{\mathtt{40}}}} = {\mathtt{48.475}}$$

$48.48

Great work Heureka

I have added this to the "Great answers to Learn from" sticky thread :)

That will not work for all decimals MG

Have a look at the instructions here

Yes, you can use Wolfram|alpha     

http://www.wolframalpha.com/input/?i=-4*cos%282*x%29-2*sin%28x%29%2B2*cos%28x%29%3D0

Put

atan(0.6009 )

Into the calculator

equals    Infinity

You know MG

I don't think that you are as good at basic algebra as you think you are.  Is it worth trying those same questions again?