1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
AVprozaik [17]
3 years ago
10

The sum of the digits of a certain two-digit number is 9. When you reverse its digits you increase the number by 63. What is the

number?
Mathematics
1 answer:
DENIUS [597]3 years ago
6 0

2-digit number is 18

Step-by-step explanation:

Let x= ten's digit and

y= one's digit

The sum of two digits is 9

so, x+y = 9

When you reverse its digits you increase the number by 63.

10y+x=10x+y+63

10y-y+x-10x=63

9y-9x=63

So, we have two equations:

x+y = 9\,\,and\,\,9y-9x=63

Solving these equations to find value of x and y:

Let:

x+y = 9\,\,\,eq(1)\\9y-9x=63\,\,\,eq(2)

Multiply eq(1) by 9 and add both equations:

9x+9y = 81\,\,\,\\-9x+9y=63\\--------\\18y=144\\y=144/18\\y=8

So, value of y=8

Now, finding value of x:

Putting value of y in eq(1)

x+y=9\\x+8=9\\x=9-8\\x=1

So, value of x=1

The value of x is 1 and value of y = 8

So, 2-digit number is 18

Keywords: Word problems

Learn more about Word Problems at:

  • brainly.com/question/1774450
  • brainly.com/question/547255
  • brainly.com/question/558692

#learnwithBrainly

You might be interested in
Shondra ordered 5 t-shirts for her friends and paid $54.95 for all of them. How much did each shirt cost her?
GarryVolchara [31]
$10.99 , divide 54.99 by 5 to get 10.99 for each shirt
5 0
3 years ago
Read 2 more answers
This is a polygon and I need help finding the missing angle ?
allsm [11]
First, you need to know that the total (degrees) of the interior angles is 360 because this is a quadrilateral.

The unnumbered angle is 109 degrees. We know this because the angle labeled 71 degrees and the unnumbered angle are supplementary. So you subtract 180 from 71 to get 109. 
180-71=109

To solve for x, we need to realize the other numbers playing into the angles' values. To make solving this easier, I'm gonna assign letters to the angles. 

(10x+6) is angle A. 

(13x-2) is angle B. 

(8x-1) is angle C.

and 109 (the one we solved) is angle D. 

We know that the total of the interior angles is 360, so we can add the 2 from angle B and the 1 from angle C to 360. This is because these numbers are subtracted from the other values. 
360+2+1=363

Now, we have to subtract the 6 from angle A from 363, because the 6 is added to the other values. 
363-6=357

Now we have to subtract 109 from 357 because you want to get the x's by themselves. Since you're solving for x. 
357-109=248

That leaves you with 248. Now you add all the x's up to get the total number of x's. You have 10x from angle A, 13x from angle B, and 8x from angle C. 
10x+13x+8x=31x

You get 31x. To get what x is, you divide 248 by 31. 
\frac{248}{31} =8

That equals 8. So now that you know that x equals 8, if you need to find the values of the angles, you just plug in the numbers into the formulas. 

(10(8))+6= 86
(13(8))-2=102
(8(8))-1=63
109

Check your work by plugging your answers in and seeing if they add up to 360. 
86+102+63+109=360

Which they should:)

So...
angle A= 86
angle B=102
angle C=63
angle D=109

and x=8



Hope this helped!!!
4 0
3 years ago
3. Russell is filling a cylinder-shaped swimming pool that
pickupchik [31]

Answer:

942 cubic feet

Step-by-step explanation:

3 0
3 years ago
Read 2 more answers
The age of some lecturers are 42,54,50,54,50,42,46,46,48 and 48 calculate the mean age and standard deviation
rjkz [21]

Answer:

Mean age: 48

Standard deviation: 4

Step-by-step explanation:

a) Mean

The formula for Mean = Sum of terms/ Number of terms

Number of terms

= 42 + 54 + 50 + 54 + 50 + 42 + 46 + 46 + 48+ 48/ 10

= 480/10

= 48

The mean age is 48

b) Standard deviation

The formula for Standard deviation =

√(x - Mean)²/n

Where n = number of terms

Standard deviation =

√[(42 - 48)² + (54 - 48)² + (50 - 48)² +(54 - 48)² + (50 - 48)² +(42 - 48)² + (46 - 48)² + (46 - 48)² + (48 - 48)² + (48 - 48)² / 10]

= √-6² + 6² + 2² + 6² + 2² + -6² + -2² + -2² + 0² + 0²/10

=√36 + 36 + 4 + 36 + 4 + 36 + 4 + 4 + 0 + 0/ 10

=√160/10

= √16

= 4

The standard deviation of the ages is 4

3 0
3 years ago
If the probability of trowing a score of seven with 2 dices is ⅛ ,what is the probability of not throwing a score of seven
V125BC [204]

Answer:

7/8

Step-by-step explanation:

because 1 - ⅛ = 7/8. which would mean the answer is 7/8

3 0
3 years ago
Other questions:
  • Help solving one more question please!Mason spent $15.85 for 3 notebooks and 2 boxes of markers.The boxes of markers cost $3.95
    8·1 answer
  • Kendall is buying a home for 119,000 she is making a 12% down payment and financing the rest with 20-year loan at 4.5% interest
    6·1 answer
  • Find the distance between the two points 4,1 and -3,-2. Show your work​
    8·1 answer
  • I need help with this math lesson ​
    9·1 answer
  • A 200 foot wire is attached from the top of a tower to a point on the ground 40 feet from the base of the tower. Find the height
    14·2 answers
  • 9x+18=-20<br><br> what does X =
    6·2 answers
  • Find the common difference of the arithmetic sequence 4,10,16
    8·1 answer
  • Mrs. Cronkhite paid $85.00 for her family of 4 to play laser tag and bowl at Evo. If each person cost the same amount to bowl an
    14·1 answer
  • 19. Frank and Jenny want to cut a plank for a sandbox they are making. If the plank is
    10·1 answer
  • To go with my last question.
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!