Here, this website explains it perfectly
Step-by-step explanation:
https://www.k5learning.com/blog/subtracting-positive-and-negative-numbers
Answer:
1.Amy should ask every 10th person leaving the school at the end of the day and Amy should ask the 50 students in her computer lab.
2.Yes,the sample is unbiased and equal to everyone.
3.200
Step-by-step explanation:
<span>The mean of a set of data is 148.87 and its standard deviation is 68.29. Find the z score for a value of 490.19
the z-score is given by:
z=(x-</span>μ<span>)/</span>σ
plugging in the values in the expression we get:
z=(490.19-149.87)/68.29
z=340.32/68.29
z=4.9835
Answer:
if a:c=2:3 andb:c=3:4therefore a:c=2:4