In a race, there are 15 runners. trophies for the race are awarded to the runners finishing in first through fourth place. in how many ways can first through fourth place be determined?

Element x decays radioactively with a half life of 8 minutes. if there are 450 grams of element x, how long, to the nearest tenth of a minute, would it take the element to decay to 37 grams?

Afamily has five members. a mom, a dad, two sisters, & a brother. the family lines up single file. what is the probabillity that the mom is at the front of the line

Manuela claims that and are congruent. which statement best describes her claim? she is incorrect because the segments do not have the same orientation. she is incorrect because the segments do not have the same length. she is correct because the segments have the same length. she is correct because the segments have the same orientation.