Eric takes a train to his parent’s house 320 miles away. If the trip takes 4 hours, what is the unit rate of the train? 1. Use the known information to write a rate.
2. The train’s rate: StartFraction 320 miles over 4 hours EndFraction
3. Write an equivalent rate with a denominator of 1.
4. Unit rate: ???

5. Check: The product of the unit rate and the total time should equal the total distance.

Which of the following lines is not parallel to the graph of y = 4x +7?

If square root x = -7, then x= -49 true or false

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.