Answer:
i think the answer is 18.15
Step-by-step explanation:
After 5 tests, her average was 88. To have a seven-test average of 90, the total must be:

Her average after 5 tests was 88. Her total score on the 5 tests is:

Subtract:

Find the average by dividing by 2:

Her average must be 95
A ) P=6n+18 where N is the number of triangles. There's always two '9's and the 6 is based on how many triangles there are.
Divide 9 into 207 then times that number by 6. You should get 138 :)x
The answer is D
Correct me if I am wrong