The Utica Boilermaker is a 15-kilometer road race. Sara is signed up to nin this race and has done the following training runs:
I.
10 miles
II.
44,880 feet
III. 15,560 yards
Which run(s) are at least 15 kilometers?

On a string instrument, the length of a string varies inversely as the frequency of its vibrations. an 11-inch string has a frequency of 400 cylces per second. find the frequency of a 10-icnch string.

Liz is shipping a package to her friend. the maximum weight of a medium flat-rate box is 20 pounds, including the box which weighs 6 ounces. write and solve an inequality to describe the possible weight ,w, of the contents that liz will ship to her friend if she must use a medium flat-rate box.

Which equation results from adding the equations in this system? x+6y=9 and -x+2y=-15