I tried my best at it and my guess is that in standard form is 0.00086
They are both equivalent to 1, so they are equal.
She would need to make an 89 on her last test. I hope this helped ^^
What I did is I put a made a list in ascending order (Least to greatest). Next, I added a number starting from 80 and then counted up. I added every number together and divided it by 5 every time I changed the number. Finally I got to the number 89 and it totaled to be 85.
Your answer will be 5xplus10
ΔABC ~ ΔADE
AC/AE = AB/AD
AC/(AC+15) = 8/18
18AC = 8(AC+15)
18AC = 8AC + 120
18AC - 8AC = 120
10AC = 120
AC = 120/10
AC = 12