Every year Bob's grandmother knits him a cozy wool sweater for his birthday. Bob's favorite color is red so she plans to buy 700 yards of thick red wool for his sweater this year. She chooses a wool that is sold in 420-foot skeins, or bundles. How many skeins should she buy? (1 yard = 3 feet)

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?