Ping pong balls sell for $.10 each.  Johnny buys 10000 for a prank.  He gets a 30% discount for buying in such large bulk.  How much does he pay?
The ping pong balls cost 10000*.10=$<<10000*.10=1000>>1000
So the discount is 1000*.30=$<<1000*.30=300>>300
So he pays 1000-300=$<<1000-300=700>>700.
#### 700