12.18 kilograms
she used 580 grams each day for each day of the week. so first do 580 X 7 =4060. then multiply 4060 by 3 because it was for three weeks. you then have 12180 grams. to go from grams to kilograms you need to divide the grams by 1000. so 12180/1000=12.18 :) i hope this helped