Plz help with the task my child is trying to do

Mathematics

2 answers:

Anna11 [10]3 years ago

4 0

9514 1404 393

Answer:

remove 7 to make the total be 6×4 = 24.

Step-by-step explanation:

The description "mean average" is redundant to no apparent purpose. "Mean" and "average" are the same thing: the total divided by the number of contributors.

If the mean of 4 cards is 6, then we require ...

6 = (total of 4 cards) ÷ 4

24 = total of 4 cards . . . . . . . multiply both sides of the equation by 4

We note that the total of all the cards shown is ...

2 + 5 + 7 + 8 + 9 = 31

In order to make the total be 24, we need to remove a card that has a value of ...

31 -24 = 7

Removing 7 will bring the total to 2 + 5 + 8 + 9 = 24, and the average to 24/4 = 6.

_____

<em>Additional comment</em>

It is worthwhile to remember the relationship between the total and the average and the number of contributors. This shows up a lot in problems involving adjusting an average or finding a value to give a certain average.

nirvana33 [79]3 years ago

3 0

Answer:

Step-by-step explanation:

First, add all the cards.

$2 + 5 + 7 + 8 + 9 = 31$

If we remove one card, the remaining four cards average will be 6, this means that the 4 remaning cards will average total will be at 24 because 6×4=24. So we need to find a value that will equal 24 if we remove that card.

The answer is 7 because

$\frac{2 + 5 + 8 + 9}{4} = 6$

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We can write the equation in point-form in this case. The equation should be:

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We'll assume that the stem diameter is normally distributed. An agronomist measured stem diameter in 8 randomly selected plants

BaLLatris [955]

Answer:

The 80% confidence interval for the population mean is (2.156, 2.394).

Step-by-step explanation:

We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

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