Answer: 505
Step-by-step explanation:
The formula to find the sample size n , if the prior estimate of the population proportion (p) is known:
, where E= margin of error and z = Critical z-value.
Let p be the population proportion of crashes.
Prior sample size = 250
No. of people experience computer crashes = 75
Prior proportion of crashes 
E= 0.04
From z-table , the z-value corresponding to 95% confidence interval = z=1.96
Required sample size will be :
(Substitute all the values in the above formula)
(Rounded to the next integer.)
∴ Required sample size = 505
The median is the middle number when the numbers are put in ascending order (lowest to highest)
1, 2, 3, 4, 4, 7
The middle numbers are 3 and 4. The number between 3 and 4 is thus the median - this number is 3.5
Answer:
2187.5 cubic meters of water
Step-by-step explanation:
Volume of rectangle = L * W * D
V = 50 * 25 * 1.75
V = 2187.5
Step-by-step explanation:
1x+2x+3x=60
x=10
2x+3x+4x=20+30+40=90
average=90÷3=30