Answer is c. so you are going to divide minutes over feet to get feet per minute. 20/18=0.9 ft per min 150/90=1.67 ft per min 90/20=4.5 ft per min 15/3 and two-thirds= 4.09
3 x 25 =75 and then 5 x 8 =40 and you would just add 75 and 40 which is where you would get 115. So the answer would be D 25 child 8 adult Hope this helps! :)