Answer:
[tex]55[/tex]
Step-by-step explanation:
We'll be using case-work to solve this problem. Let's call the ones digit of the telephone number [tex]B[/tex] and the tens digit [tex]A[/tex]. Each telephone number can be represented as [tex]AB[/tex].
Since the question states that numbers that are smaller when their digits are reversed are not used, we have the following inequality:
[tex]B\geq A[/tex]
This is because if [tex]A>B[/tex], the number would become smaller when [tex]A[/tex] and [tex]B[/tex] are switched in [tex]AB[/tex]. However, if [tex]A=B[/tex] or [tex]B>A[/tex], the number will not become smaller.
Let's work our way up starting with [tex]A=0[/tex]. If [tex]A=0[/tex], there are 10 other numbers (0-9) that we can choose for [tex]B[/tex] that adhere to the condition [tex]B\geq A[/tex]:
[tex]0B,\\01, 02, 03,...[/tex]
Therefore, there are 10 possible telephone numbers when the tens digit is 0.
Repeat the process, now assigning [tex]A=1[/tex]. Now, we only have the digits 1-9 to choose from for [tex]B[/tex], since [tex]B[/tex] needs to be greater than or equal to A. Therefore, there are 9 possible telephone numbers when the tens digit is 1.
This pattern continues. As we work our way up through the cases (when increasing [tex]A[/tex] by 1), the number of possible telephone numbers decreases by 1, since there becomes one less option for [tex]B[/tex].
The last case would be [tex]A=9[/tex] in which case there would only be one option for [tex]B[/tex] and that would be 9.
Since there are 10 cases (0-9), add up the possible telephone numbers for each case:
[tex]\displaystyle \sum_{n=1}^{10}n=1+2+3+4+5+6+7+8+9+10=\boxed{55}[/tex]
Alternatively, recall that the sum of this series can be found using [tex]\frac{n(n+1)}{2}[/tex], where [tex]n[/tex] is the number of values in the set. In this case, [tex]n=10[/tex], and we have:
[tex]1+2+3+4+5+6+7+8+9+10=\frac{10(11)}{2}=\frac{110}{2}=\boxed{55}[/tex]
I need help ASAP!!Explain the answer
Answer:
volume=pi times r^2 height÷3.
r is the radius, or in this case 4yd. height is 10yd. pi is 3.14
Here are the steps:
3.14r^2 height÷3
3.14×4^2 10÷3
=167.55
final answer rounded to the nearest tenth: 167.6
I apologize for getting the math wrong the first time. My formula was correct, but I needed to double check my calculations. I'm certain this is the right answer.
PLS HELP ME ON THIS QUESTION I WILL MARK YOU AS BRAINLIEST IF YOU KNOW THE ANSWER PLS GIVE ME A STEP BY STEP EXPLANATION!!
Answer:
A. (3, 5)
Step-by-step explanation:
J is currently at (3, -5). As it's reflected, the x coordinate will stay the same, and the y coordinate will switch signs since we're going from negative to positive. Our answer is (3, 5).
PLS HELP ME ON THIS QUESTION I WILL MARK YOU AS BRAINLIEST IF YOU KNOW THE ANSWER PLS GIVE ME A STEP BY STEP EXPLANATION!!
Carl and Nicole are raising money to purchase basketballs for their school's team. The more money they raise, the more basketballs they will be able to purchase for the school. What is the independent variable?
A. the number of students on the team
B. the number of students in the school
C. the amount of money that is raised
D. the number of basketballs
Answer:
C. The amount of money that is raised
Step-by-step explanation:
in the equation, it is the amount of money that is raised because how much money is raised affects the amount of basketballs purchased.
In other words, if the amount of money is less, then there will be less basketballs purchased as a result. If the amount of money is more, then there will be more basketballs purchased as a result.
Answer:
C. the amount of money that is raised
Step-by-step explanation:
I always think of it like this:
independent: money they are raising
dependent: the amount of a certain item the money is being used on
A city has a property tax rate of 70 mills and an assessment level of 40%.
What is the effective property tax rate? Round your answer to the nearest
tenth of a percent.
Mill rate is a tax rate—the amount of tax payable per dollar of the assessed value of a property. Mill is derived from the Latin word millesimum, meaning thousandth. As used in property tax, 1 mill is equal to $1 in property tax levied per $1,000 of a property's assessed value.
Simplify. (x2+2x-4)+(2x-5x-3)
Answer:
Step by Step Solution
More Icon
STEP
1
:
3
Simplify ——
x2
Equation at the end of step
1
:
3
((((2•(x2))-5x)-——)+2x)-3
x2
STEP
2
:
Equation at the end of step
2
:
3
(((2x2 - 5x) - ——) + 2x) - 3
x2
STEP
3
:
Rewriting the whole as an Equivalent Fraction
3.1 Subtracting a fraction from a whole
Rewrite the whole as a fraction using x2 as the denominator :
2x2 - 5x (2x2 - 5x) • x2
2x2 - 5x = ———————— = ———————————————
1 x2
Equivalent fraction : The fraction thus generated looks different but has the same value as the whole
Common denominator : The equivalent fraction and the other fraction involved in the calculation share the same denominator
STEP
4
:
Pulling out like terms
4.1 Pull out like factors :
2x2 - 5x = x • (2x - 5)
Adding fractions that have a common denominator :
4.2 Adding up the two equivalent fractions
Add the two equivalent fractions which now have a common denominator
Combine the numerators together, put the sum or difference over the common denominator then reduce to lowest terms if possible:
x • (2x-5) • x2 - (3) 2x4 - 5x3 - 3
————————————————————— = —————————————
x2 x2
Equation at the end of step
4
:
(2x4 - 5x3 - 3)
(——————————————— + 2x) - 3
x2
STEP
5
:
Rewriting the whole as an Equivalent Fraction :
5.1 Adding a whole to a fraction
Rewrite the whole as a fraction using x2 as the denominator :
2x 2x • x2
2x = —— = ———————
1 x2
Polynomial Roots Calculator :
5.2 Find roots (zeroes) of : F(x) = 2x4 - 5x3 - 3
Polynomial Roots Calculator is a set of methods aimed at finding values of x for which F(x)=0
Rational Roots Test is one of the above mentioned tools. It would only find Rational Roots that is numbers x which can be expressed as the quotient of two integers
How much cement is needed for a hole 0.4m wide and 1m long.
Answer:
its 80 meters longs
Step-by-step explanation:
if it is wrong just go look it up
The curved part of this figure is a semicircle.
What is the best approximation for the area of this figure?
18+24.25π units²
18+12.125π units²
36+24.25π units²
36+12.125π units²
Answer:
carna estralia con frema es 36+12.125tt ernits es answeana
Step-by-step explanation:
Answer:
18+12.125π units²
Suppose a study finds that the correlation coefficient relating job satisfaction to salary is r=1. Which of the following are the proper conclusions?
I. High salary causes high job satisfaction.
II. Low salary causes low job satisfaction.
III. There is a very strong association between salary and job satisfaction.
I and II only
I, II and III
III only
I only
Answer:
its I, II and III.
Step-by-step explanation:
r values are from -1 to 1, if the value is 0 means there's no connection between values of variables, if its lower than 0, if the value of variable goes up the other goes down, if its higher than 0, than if one value of variable increases than the value of other variable increases too. the closer to 1 the stronger the association.
What is the equation of the line that passes through the point (3,-7) and has a undefined slope
Answer:
x = 3
Step-by-step explanation:
A vertical line has undefined slope. Its equation is of the form x=c, for some constant c.
Line through (3, -7)To make sure the line passes through a point with an x-coordinate of 3, the constant in the equation must be 3:
x = 3 . . . . . . vertical line through (3, -7)
If x−2/4=2, then x=10
Answer:
True.
Step-by-step explanation:
[tex]\frac{(10)-2}{4}=2\\\\\frac{8}{4}=2\\\\2=2[/tex]
when graphing y=-2x+10, is it a line that shows only one solution to the equation, all solutions, or shows the y-intercept?
Answer:
there is always a y-intercept in all graphs.
Step-by-step explanation:
be it a line graph, quadratic graph or cubic graph. all graphs will definitely have a y-intercept. and in this case, since y=mx + c where c is the y-intercept. the y intercept of this graph is 10
compare the values of the 7s in the number 4,877,034
Answer:
4,877,034=70,000
4,877,034=7,000
Explanation:
Place value is the value of each digit in a number. For example, the 5 in 350 represents 5 tens, or 50; however, the 5 in 5,006 represents 5 thousands, or 5,000. It is important that children understand that whilst a digit can be the same, its value depends on where it is in the number.
Hope this helps <3
Need thanks? Comment /hearthelp
type the correct answer in each box. use numerals instead of words. if necessary, use / for the fraction bar
HELP HELP
Answer:
Hello,
Step-by-step explanation:
f(x)=x+3 if -3≤x≤-1
(the line is passing trough (-3,0) and (-1,2) ==> y-0=(x+3)((2-0)/(-1+3) ==> y=x+3
f(x)=5 if -1≤x≤1
4) In the proof below, what is the missing reason?
9514 1404 393
Answer:
(c) CPCTC
Step-by-step explanation:
Even if you don't know the meaning of CPCTC, you can eliminate the other choices because they refer to the whole triangle, not two corresponding angles.
Angles B and D are corresponding angles in the congruent triangles. The reason they are congruent is ...
Corresponding Parts of Congruent Triangles are Congruent (CPCTC)
Write the following as an algebraic expression. Then simplify.
The sum of two consecutive odd integers if the first integer is x.
Answer:
2x+2
Step-by-step explanation:
The first odd integer is x
The second odd integer is x+2
The sum
x+ x+2
2x+2
IssaC is now x years old. Erika is 7 years older than Issac. In terms of how old was Erika 4 years ago ?
Answer:
Isaac = x
Step-by-step explanation:
Erika is 3y older than Isaac
Isaac is x years old
Answer: x+3
Work Shown:
x = Issac's age right now
x+7 = Erika's age right now
(x+7)-4 = x+3 = Erika's age four years ago
18 cards are numbered from 11 to 29 if one card is chosen at random, what is the probability that if contains the digit
please help me asap
Answer:
Does the answer help you?
write each number as a reduced fraction or mixed number. A. 16/24 B. 15/24. C. 4%
Answer:
A.1/3 B.5/8 C.1/25
Step-by-step explanation:
just simplify it down to the lowest
Answer:
Ä. 16/24 as reduced fraction = 2/3
B. 15/24 as reduced fraction= 5/8
Amy walks from point A to point B along the segment AB. Fraser walks from point A to point C along the segment AC. Which statement is correct?
Your answer:
Amy walks a distance equal to the diameter, and Fraser walks a distance equal to the radius of the lawn.
Both Amy and Fraser walk distances equal to the radius of the lawn.
Both Amy and Fraser walk distances equal to the diameter of the lawn.
Amy walks a distance equal to the radius, and Fraser walks a distance equal to the diameter of the lawn.
Answer: the answer is
the option
B) Amy walks a distance equal to the radius, and Fraser walks a distance equal to the diameter of the lawn.
Step-by-step explanation:
square of 5x+1 by 5x
Answer:
5x(5x+1)^2
= 5x(25x^2+10x+1)
= 125x^3+50x^2+5x
3x + 5 = x - 3
What is the solution to this equation? Show all the steps you used to solve this equation.
Answer:
x = -4
Step-by-step explanation:
3x + 5 = x - 3
Subtract x from each side
3x+5-x = x-3-x
2x+5 = -3
Subtract 5 from each side
2x+5-5 = -3-5
2x = -8
Divide each side by 2
2x/2 = -8/2
x = -4
As a burglar reaches for something on the mantel, accidentally knocks over a clock. It falls to the floor, breaks, and stops. The next morning, however, pol.ice aren't able to determine what time the robbery took place. Why not?
Answer: There is no way of finding out if the clock worked before then, and if it stopped at P.m or A.m.
Step-by-step explanation:
Let's say the robber broke the clock at 3 a.m, the police would first of all not have any idea if the clock was indeed broken before the robber knocked it over, and the clock has no way of saying whether it was broken at 3 a.m. or 3 p.m, therefore it's rendered useless.
PLEASE HELP!!
Find the area of the sector.
Answer:
B.
[tex] \frac{275\pi}{6} {m}^{2} [/tex]
Step-by-step explanation:
[tex]area \: of \: sector \: is \\ \frac{the \: angle}{360} \times \pi {r}^{2} \\ hence \: we \: have \\ \frac{165}{360} \times {(10m)}^{2} = \frac{275\pi}{6} {m}^{2} [/tex]
in a class ,ratio of the number of girls to boys is13:7 , find the percentage of boy
Help pls! Gotta be done before I go to work :((
Answer:
A = 104 ft²
Step-by-step explanation:
The area (A) of a trapezium is calculated as
A = [tex]\frac{1}{2}[/tex] h (b₁ + b₂ )
where h is the perpendicular height and b₁, b₂ are the parallel bases
Here h = 8, b₁ = 10 + 6 = 16, b₂ = 10 , then
A = [tex]\frac{1}{2}[/tex] × 8 × (16 + 10) = 4 × 26 = 104 ft²
A school bought 45 band uniforms and 18 musical instruments. If the
uniforms cost $89 each, what was the total cost of the uniforms?
Answer:
45 times 89
Step-by-step explanation:
The instuments are irrelevant and are only there to distract you.
Answer:
45 times 89 equals 4005
Step-by-step explanation:
PLS HELP!!
what is the value of x?
log2(x+7) = 2
Answer: Choice A) -3
Work Shown:
[tex]\log_{2}(x+7) = 2\\\\x+7 = 2^2\\\\x+7 = 4\\\\x = 4-7\\\\x = -3\\\\[/tex]
Which leads us to choice A. In the second step, I used the rule that [tex]\log_b(y) = x[/tex] is equivalent to [tex]y = b^x[/tex]. For each equation, the b is the base. Note how logs undo exponents and vice versa.
Answer:
-3
Step-by-step explanation:
log2(x+7) = 2
Raise each side by base 2
2^log2(x+7) = 2^2
x+7 = 4
Subtract 7 from each side
x+7-7 = 4-7
x=-3
25 points, choices in photo
Which of the following accurately shows the first step when solving the following system of equations by substitution?
I would go with C as a first step
The correct answer is C (that is equating f(x) and g(x))
How to solve a quadratic and linear equation?A quadratic polynomial has highest degree 2 and a linear polynomial has highest degree 1.
In geometric sense, solving them means finding the point of intersection of curves:
In X-Y plane, these polynomials can be written as:
[tex]y=-x^{2} +2x+3\\y=-2x+3[/tex]
Taking the value of y from second equation and substituting it in first equation we get,
[tex]-x^{2} +2x+3=-2x+3[/tex]
Therefore, with the above procedure, we got the first step of solving the equations with the help of substitution.
To know more about polynomials refer to:
https://brainly.com/question/9438778
#SPJ2
Will Mark Brainnlest Please help me
Answer:
sory
Step-by-step explanation:
soryuuuiuuuiiiiiiijjjjkkkkkj
