Answer equals 1
Step-by-step explanation:
It's not a hard question
Step-by-step explanation:
step 1. 12x - 15 - 12x = 7x + 20
step 2. 12x - 12x - 15 = 7x + 20 (grouping of terms)
step 3. -15 = 7x + 20 (adding like terms)
step 4. -35 = 7x (subtract 20 from both sides)
step 5. this step is incorrect.
step 6. -5 = x ( divide both sides by 7)
step 7. x = -5 (put the variable first).
Answer:
Last option?
Step-by-step explanation:
ax+by=c
4x+6y=60
a=4
b=6
c=60
Answer:
Mean = 30
standard Deviation = 2.74
Step-by-step explanation:
Formula
mean = np
Standard Deviation = 
from the question = 40
P = 75% or 0.75
q = 1 - p = 1 - 75% or 1 - 0.75
To find mean
mean = 40 x 0.75
= 30
For Standard Deviation (SD)
Standard Deviation =
= 
= 
:. Standard Deviation = 2.74