None. Halfcrowns were last minted in 1967. Prior to decimalisation in 1971, there would have been 8 Halfcrowns in one British Pound.
7.95 crowns
As of July 2014, 1 US dollar is equivalent to 20.41 Czech Republic Korunas (or "crowns").
Half a dollar is fifty cents.
Half a dollar is fifty cents.
2 half dollars
It's right in the name "Half-dollar" half of a dollar is 50 cents.
150 grooves
There are 150 ridges on the half dollar coin.
There are twenty half dollars in a ten dollar bill.
At the time of writing 1 AUD is about 6.8 Kronor.
Two quarters equal one half dollar.
There are 5 dimes in a half dollar.