Answer:
148
Step-by-step explanation:
Average = sum of numbers /total numbers
let x = 5th number
123.2 = (118+ 128 + 124,+ 98 + x) / 5
123.2 = (468 + x) / 5
Multiply both sides by 5
616 = 468 + x
x = 148
We can pick a common denominator by multiplying.
3*7/5*7= 21/35
4*5/7*5= 20/35
We have our common denom is 15.
Our fractions: 21/35 and 20/35
5x -15 + 3 -8x = 13
5x -12 -8x = 13
5x -8x =13 -12
-3x = 1
x = -1/3
Answer: r = 3
Step-by-step explanation:
Step 1: Cross-multiply.
2r = 12/18
(2)*(18)=12*r
36=12r
Step 2: Flip the equation.
12r=36
Step 3: Divide both sides by 12.
12r/12 = 36/12
r = 3
21x^2
you CAN'T factor 21x^2
