Answer i've done the math multiple times and everytime i get the answer 21,950. i don't think i'm doing the math wrong, maybe try asking the teacher or whoever is the one grading it cause it could be a typo or something like that.
Step-by-step explanation:
Answer:
He can grade 1.25 assignments in 1 minute.
Step-by-step explanation:
Because the teacher can grade 25 assignments in 20 minutes, we can dive 25 by 20 to get the constant rate.

So he can grade 1.25 assignments in 1 minute.
Answer:
k = 6 : 5 : 4
Step-by-step explanation:
BC : AB : AC = 18 : 15 : 12 = 6 : 5 : 4
EF : DE : DF = 12 : 10 : 8 = 6 : 5 : 4
2133.6 centimeters i hope i help you