steve the Stamp Collector has a stamp collection of 210 stamps. 3/7 of Steve's collection are 1st class stamps, all of which are red. This is 6/7 of the total number of red stamps. How many red stamps in total are there?

Afootball quarterback has two more chances to throw a touchdown before his team is forced to punt the ball. he misses the receiver on the first throw 25% of the time. when his first throw is incomplete, he misses the receiver on the second throw 15% of the time. what is the probability of not throwing the ball to a receiver on either throw?