Aftershocks occur after the most major part of an earth quake happens. Earthquakes occur at fault lines near the tectonic border. They occur because of the sudden movement for staying rigid while they were edging closer and closer. So the sudden movement releases a large amount of tension buried deep below the earth creating or resulting in an earthquake.
Multiply the first equation by 7 and the second equation by 2, and then add.
Step-by-step explanation:
2f - 5g=-9
-7f + 3g=4
To eliminate any variable , we need to make the coefficients same with different sign and add it
the coefficient of 'f' in first equation is 2
the coefficient of 'f' in second equation is -7
We already have different sign so we make the coefficients same
To make the coefficient same , we multiply the first equation by 7 and second equation by 2
So equation becomes
14f - 35g = -63
-14f + 6g = 8
Now when we add both equations, 'f' gets cancelled
-29g = -55
Answer:
0
Step-by-step explanation:
Answer:
Step-by-step explanation:
We are given the following in the question:
Significance level = 0.01
Width of interval = 0.1
Population variance = 
We have to find the sample size so that the width of the confidence interval is no larger than 0.1

Formula for sample size:

where E is the margin of error. Since the confidence interval width is 0.1,

Putting these values in the equation:

So, the above expression helps us to calculate the sample size so that the width of the confidence interval is no larger than 0.1 for different sample variances.
X=31 because
(2x)+(x-3)=90
2x+x-3=90
3x-3=90
3x=93
x=31