Given:
The frequency distribution table.
To find:
The mean average score on a test.
Solution:
The frequency distribution table is
x a xa
y b yb
z c zc
Sum a+b+c xa+yb+zc
Now, the mean average score on the test is
Therefore, the mean average score on the test is .
Degree of a polynomial gives the highest power of its terms. Yes there is a difference between the degrees of sum and difference of the polynomials.
<h3>What is degree of a polynomial?</h3>Degree of a polynomial is the highest power that its terms pertain(for multi-variables, the power of term is addition of power of variables in that term).
Thus, in , the degree of the polynomial is 3 as the highest power in its terms is 3.
(power and exponent are same thing)
<h3>What are like terms?</h3>Those terms which have same variables raised with same powers.
For example, and
are like terms since variable is same, and it is raised to same power 3.
For example and
are not like terms as the variables are same but powers aren't same.
The given polynomials are:
Their sum is
(only like terms' coefficients can be added (or subtracted) for addition or subtraction of them )
The sum's degree is 7
Their difference is:
Difference's degree is 5
Thus, both's degrees are not same.
Thus, Yes there is a difference between the degrees of sum and difference of the polynomials.
Learn more about subtraction of polynomials here:
Answer:
The number of pumps and hours) vary inversely.
The constant of variation is 20.
Step-by-step explanation:
Let x be number of pumps and y be number of hours.
We have been given that working together, two identical water pumps can fill a pull in 10 hours. This means while working alone the pumps will take 2 times as much time to fill the tank.
As we increase number of pumps (x), number of hours (y) is decreasing and as we decrease x our y is increasing, therefore, number of pumps (x) and hours (y) vary inversely.
Since we know that an inversely proportion equation is in form: , where, k is constant of variation.
Upon substituting our given values in above equation we will get,
Upon multiplying both sides of our equation by 2 we will get,
Therefore, the constant of variation is 20.