2p+6a=$14
3p+9a=$21
3p+9a=21
Subtract 9a
3p=21-9a
divide all by 3
p=7-3a
plug it into start equations
2p+6a=14
2(7-3a)+6a=14
14-6a....+6a=14
this zeroes out...
Answer:
0.4494
Step-by-step explanation:
Given :
marks number of students
20-29 8
30-39 12
40-49 20
50-59 7
60-69 3
The range Coefficient is obtained thus :
Range Coefficient = (Xm - Xl) / (Xm + Xl)
Where ;
Xm = Mid value of highest class = (60+69)/2 = 64.5
Xl = Mid value of lowest class = (20+29)/2 = 24.5
Range Coefficient = (64.5 - 24.5) / (64.5 + 24.5)
Range Coefficient = 40 / 89 = 0.4494
Answer:
24 Domain: s>=2 or s<=-2
25. 3x^2 +14x +10
26. x^2 -2x+5
Step-by-step explanation:
24. Domain is the input or s values
square roots must be greater than or equal to zero
s^2-4 >=0
Add 4 to each side
s^2 >=4
Take the square root
s>=2 or s<=-2
25. f(g(x)) stick g(x) into f(u) every place you see a u
f(u) = 3u^2 +2u-6
g(x) = x+2
f(g(x) = 3(x+2)^2 +2(x+2) -6
Foil the squared term
= 3(x^2 +4x+4) +2x+4-6
Distribute
= 3x^2 +12x+12 +2x+4-6
Combine like terms
=3x^2 +14x +10
26 f(g(x)) stick g(x) into f(u) every place you see a u
f(u) = u^2+4
g(x) = x-1
f(g(x) = (x-1)^2 +4
Foil the squared term
= (x^2 -2x+1) +4
= x^2 -2x+5
D. X = 10
6x-20= 40
6x=40+20
6x=60
X=10
Answer:
Modification has not reduced the number of accidents.
Step-by-step explanation:
A B C D E F G H
Before modification 5 7 6 4 8 9 8 10
After modification 3 7 7 0 4 6 8 2
Difference -2 0 1 -4 -4 -3 0 -8
Mean of differences 
Standard deviation of differences = 
Formula of paired t test :
Df = n-1 = 8-1 =7
t critical> t calculated
So, We failed to reject null hypothesis
Hence modification has not reduced the number of accidents.
