Let sum of 3 numbers be x.
Average of 3 numbers and 8 =

25 =

100 = x +8
x= 92.
The sum of 3 numbers is 92.
Answer:
x=(8/3, infinity)
Step-by-step explanation:
-3x+8<15-3x+8
-3x+8<-3x+23
8<23
15-3x+8<15
23-3x<15
-3x<-8
x>8/3
Therefore, x=(8/3, infinity)
Answer:
4) choice a 30%
5) choice b 62.5%
Step-by-step explanation:
4) 3/10 = 0.30 or 30%
5) 5/8 = 0.625 or 62.5%
X^2 = 81...take the square root of both sides, eliminating the ^2
x = (+-) sqrt 81
x = (+-) 9
answers are : -9 and 9