Answer:
nine hundred five thousand two hundred thirty-eight
Let 
be the 20 marks of the boys, and 
be the 10 marks of the girls.
We know that the global mean was 70, meaning that
Multiplying both sides by 30 we deduce that the sum of the scores of the whole classroom is
By the same logic, we work with the marks of the boys alone: we know the average:
And we deduce the sum of the marks for the boys:
Which implies that the sum of the marks of the girls is 
And finally, the mean for the girls alone is
Answer:
-2
Step-by-step explanation:
In the picture
Answer:
b. type II
Step-by-step explanation:
given that food inspectors inspect samples of food products to see if they are safe. This can be thought of as a hypothesis test with the following hypotheses.
H0: the food is safe
Ha: the food is not safe
It was concluded from the hypothesis test that the food is safe while it was not actually safe.
This is a case of false acceptance of null hypothesis when it is false.
In hypothesis test, there are two errors. a type I error is the rejection of a true null hypothesis while a type II error is the non-rejection of a false null hypothesis
So this is type II error because we did not reject a false null hypothesis.
Answer: Eighty-seven thousand-fifty five
Step-by-step explanation:
