Answer:
7
Step-by-step explanation:
7/7=1
14/7=2
Also, not being mutually exclusive could be proven by showing there are values in the intersection: A ∩ B
Answer: The sample mean 
Step-by-step explanation:
The confidence interval is given by :-
Sample mean ± Margin of error
Given : The scores on a standardized test are normally distributed. If a random sample of standardized test scores is taken and the confidence interval is (497,537).
i.e. Sample mean - Margin of error = 497 ..(i)
Sample mean + Margin of error=537 ..(ii)
Adding (1) and (2), we get
2 (Sample mean) = 1034
⇒Sample mean = 517
Hence, the sample mean 
100% - 25% = 75%
52.50 = 75% of what number?
52.50 = 0.75x
Let x = original cost
52.50 ÷ 0.75 = x
70 = x
The original cost was £70.