Well firstly you need to find what 7% of 250 is:
250 x .07 = 17.5
(.07 is 7% in decimal form)
and then you add that to the original value:
250+17.5= 267.5
Now that you've found the price with the 7% increase you find the half-off price.
267.5 / 2 = 133.75
There you go! The price of the coat would now be $133.75.
Hope this helped :)