SOLUTION: what is 200 less than half of a number

To make a quantity become less than it is, 

1. you write the quantity down 

and then 

2. you subtract from it.

We want to make 'half of a number' less than it is, so

1. we write down 'half of a number' which is x.

So we write down

x

2. Then we subtract 200 from it

x - 200

[Caution: don't make the mistake of writing .
Always begin with what you want to make less (or greater
in some other problems)]

Edwin