Answer:
Answer OPTION C
AT LEAST... means that she needs 80% and more
Meaning its must be equal to 80% or greater than 80%
Average has to do with Mean.
Her mean would have to be
The sum of the 3 last algebra tests plus the unknown one she's supposed to have to complete 80%
So
Thatll be
80+75+86 + x /(4) ≥ 80
241 + x/(4) ≥80
Option C
