Answer:
x= 4/5
y= 2/5
Step-by-step explanation:
3x-y=2
2x+y=5
solve them so that they are in y=mx+b form
3x-y-3x=2-3x
-y= -3x+2
y= 3x -2
2x+y -2x= 2-2x
y= -2x+2
now use the substitution method to get your points
3x -2= -2x+2
3x -2+2= -2x+2+2
3x= -2x+4
3x+2x= -2x+4+2x
5x=4
x= 4/5
now substitute x into any of the 2 equations
y= 3x -2
y= 3(4/5) -2
y= 2 2/5 -2
y= 2/5
Hope this helped!
Answer: B. 264
Step-by-step explanation:
Formula to calculate the sample size 'n' , if the prior estimate of the population proportion (p) is available:
, where z = Critical z-value corresponds to the given confidence interval
E= margin of error
Let p be the population proportion of clear days.
As per given , we have
Prior sample size : n= 150
Number of clear days in that sample = 117
Prior estimate of the population proportion of clear days = 
E= 0.05
The critical z-value corresponding to 95% confidence interval = z*= 1.95 (By z-table)
Then, the required sample size will be :
Simplify ,
Hence, the sample size necessary to construct this interval =264
Thus the correct option is B. 264
Answer:
a
Step-by-step explanation:
Answer:
x = 7
Step-by-step explanation:
=> 9/72 = 3x-20/56
=> 9×45/72 = 3x-20
=> 27/3 = x
=> x = 7