Answer:
3=20
4=15
5=12
Step-by-step explanation:
In total, Kay took 5+14+2=21exams. she got 80%-90% on 14 of them. the probably is 14/21 which is 2/3. Therefore, the probability of Kay getting 80%-90% on her next exam is 2/3 or 66.6%
The fewest number of expressions is 3.
Answer:

Step-by-step explanation:
As the triangles are similar :
45/55 = (12x - 3)/143
9/11 = (12x - 3)/143
9 x 13 = 12x - 3
12x = 117 + 3
12x = 120
x = 10
R=-4
desmos is a good app to check out these priblems (i do it all the time)