Answer:
Step-by-step explanation:
Given that
Population mean 
std deviation
= 12
sample size n =36
Sample mean = 

(Two tailed test)
Mean difference = 7
Std error =
Since population std dev is known and n>30 we use Z test
Z statistic = 
p value <0.001
Since p value is <0.01, at 1% significance level, we reject H0.
There is significant difference between sample mean and population mean.
Answer:
?
Step-by-step explanation:?
Answer:
14
Step-by-step explanation:
28m + 21 = 413
28m = 413 - 21
= 392
m = 392/28
= 14
Therefore m is 14 :)
Answer:
Profit = $(700 - 42x - 56y)
Step-by-step explanation:
For large candles, the selling price is $10 and its making cost is $x.
So, by selling a large candle the profit is $(10 - x)
Again for small candles, the selling price is $5 and its making cost is $y.
So, by selling a small candle the profit is $(5 - y)
Therefore, in a sell of 42 large candles and 56 small candles the total profit will be, P = 42 (10 - x) + 56 (5 - y)
⇒ P = 420 - 42x + 280 - 56y {Applying distributive property}
⇒ P = $(700 - 42x - 56y) (Answer)