If john ran a 5 kilometers marathon how long was the meters

Really need on these. i have no idea what to do

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle.he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field

How many 2/5s are in 1 and 1/2 plz someone me right now