Select the pair of numbers that have: a sum of 45 and a difference of 5.
a) 26 and 19
b) 25 and 20
c) 24 and 21
d) 26 and 21

Two cyclists 84 miles apart start riding toward each other at the samen time. one cycles 2 times as fast as the other. if they meet 4 hours later what is the speed (in miles) of the faster cyclists

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.

Stefanie is painting her bedroom. she can paint 2 1/3 square feet in 4/5 of an hour. how many square feet can she paint in one hour?