Laura is three times as old as luci. in 5 years, the sum of their ages will be 30. what are the current ages of laura and luci? and
four years ago peter was three times as old as sylvia, and in 5 years the sum of their ages will be 38 years. find their present ages.

answer under 10 min

If f(x)= 3x+6 which of the following is the inverse of f(x)

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

Of the ones listed here, the factor that had the greatest impact on the eventual destruction of native americans' ways of life was the development of the a) automobile. b) highway. c) railroad. d) steamboat.