Sam is buying Christmas presents at the school store. Sam buys a Sabercat mask for his sister for$6.25 and a SJH T-shirt for his brother for $18.75. If Sam has a coupon for 20% off
his total purchase, how much will he have to pay?

Simplify (a/b - b/a) times (a - a^2/a+b) a - a^2/a=b is a mixed number

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.

If the discriminant if a quadratic equation is 4 which statement describes the roots?