At a rap concert, the ratio of the number of boys to the number of girls is 9: 5. If there are 320 more boys than girls, how many boys and how many girls are at the concert?

Rick is driving to his uncles house in greenville,which is 120 miles from ricks town .after covering x miles rick she's a sign stating that greensville is 20 miles away. which equation when solved will give the value of x. a: x+120 = 20 b: x x120 =20 c: x +20 equals 120 d: x x20= 120