All exercises involve the same concept, so I'll show you how to do the first, then you can apply the exact same logic to all the others.
The first thing you need to know is that, when a certain quantity multiplies a parenthesis, you can distribute that number to every element in the parenthesis. This means that

So,
is multiplying the parenthesis involving
and
, and we distributed it:
multiplies both
and
in the final result.
Secondly, you have to know how to recognize like terms, because they are the only terms you can sum. Two terms can be summed if they have the same literal expression. So, for example, you cannot sum
, and neither
exponents count.
But you can su, for example,

or

So, take for example exercise 9:

We distribute the 1.2 through the first parenthesis:

And you can distribute the negative sign through the second parenthesis (it counts as a -1 to distribute):

So, the expression becomes

Now sum like terms:

Answer:
Australia.
Bangladesh.
England.
India.
New Zealand.
South Africa.
Sri Lanka.
West Indies.
Step-by-step explanation:
none
hope this helps
Answer:
And we can find this probability using the complement rule and the normal standard table or excel:
The firgure attached illustrate the problem
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the retirement savings of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability using the complement rule and the normal standard table or excel:
The firgure attached illustrate the problem
Answer:
1. Find the common denominator.
2. Multiply everything by the common denominator.
3. Simplify.
4. Check the answer(s) to make sure there isn't an extraneous solution.
Step-by-step explanation:
Hope this helps!
9514 1404 393
Answer:
29
Step-by-step explanation:
The third in sequence will be the middle one, the average value of all the numbers in the sequence. That average is the sum (145) divided by the number of numbers (5).
third number = 145/5 = 29