contestada

Samantha ran on a fitness track for 20 ​min, and then walked for 15 min. Her running rate was 230 ft per minute faster than her walking rate. If she ran and walked a total of 16 comma 150 ​ft, how fast did she​ run?

Respuesta :

sqdancefan

Answer:

  560 ft/min

Step-by-step explanation:

Let r represent Samantha's running rate in feet per minute. Then r-230 is her walking rate. We can use the relation ...

   distance = speed × time

to write an equation for the total distance Samantha went.

  20r + 15(r -230) = 16150

  35r - 3450 = 16150 . . . . eliminate parentheses, collect terms

  35r = 19600 . . . . . . . . . . add 3450

  r = 560 . . . . . . . . . . . . . . divide by the coefficient of r

Samantha ran 560 feet per minute.

Otras preguntas