Ella bought some keychain and spent a total of $24. each keychain cost the same hole dollar amount. she bought between seven and 11 keychains. how many keychains did ella buy

The ratio of rock songs to dance songs on jonathan’s mp3 player is 5: 6. the total number of rock and dance songs jonathan has is between 101 120. how many rock songs does he have?

17 in long 1.3 ft wide and 8in high what is the volume

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $32.09. find the probability that a randomly selected bill will have an amount greater than $155, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?