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
Katena32 [7]
3 years ago
15

a certain number of two digit is three times the sum of its digit and if 45 added to it the digit will be reversed find the numb

er ?​
Mathematics
1 answer:
bogdanovich [222]3 years ago
5 0
· Author has 184 answers and 67.6K answer views
Let the number be (10 x + y)

Then, 10 x + y = 3 * (x + y) (given)

Or, 10 x + y = 3 x + 3 y

Or, 10 x - 3 x = 3 y - y

Or, 7x = 2 y

Or, x = 2 y / 7 ( Eq. 1)

Also, 10 x + y + 45 = 10 y + x ( given)

Or, 10 x - x = 10 y - y - 45

Or, 9 x = 9 y - 45 ( Eq. 2)

Substituting the value of x from (Eq. 1) in (Eq. 2), we have:

9 * 2 y / 7 = 9 y - 45

Or, (9 y ) - (18 y / 7) = 45

Or, 63 y - 18 y = 315

Or, 45 y = 315

Or, y = 7

From (Eq. 1),

x = 2 * 7 / 7 = 2

So, the number is 10 x + y = (10 * 2) + 7 = (20 + 7) = 27

Answer

Check:

Sum of the digits = 2 + 7 = 9

9 * 3 = 27 ✓

Adding 45 to the number 27, we get 72. So, the digits get reversed.
You might be interested in
Ari lives 4/5 of a mile from the park she has already walked 3/4 of the way to the park. How far has ari walked
Olin [163]
3/4 of 4/5 = 3/4 x 4/5 = 12/20 = 3/5 of a mile (= 1056 yards)
3 0
2 years ago
A theatre has seats arranged in rows of 24, 382 people attend a show at the theatre. What is the smallest number of rows that is
kipiarov [429]

Answer:

A minimum of 16 rows are needed

Step-by-step explanation:

Here, we want to calculate the number of rows minimum that could seat 382 people in rows of 24 seats.

Mathematically, what we need to do here is to make a division.

We shall divide the number of people by the number of seats in a row so that we can get the number of rows needed.

Mathematically, that would be; 382/24 = 15 22/24

We are looking at a minimum number.

So we can see that 15 rows will be filled, with an extra 22 seats in the next row leaving only 2 seats in the next row unoccupied.

So we can see that the minimum number of rows required is 16 rows

3 0
3 years ago
Please help<br> do step by step<br> I learn diff
Lesechka [4]
1.5 use a calculator
6 0
2 years ago
Read 2 more answers
Which of the following numbers is closest to 6?
vichka [17]
B because all the others are further from 6
5 0
2 years ago
Read 2 more answers
Kevin hiked up lambs Canyon and two hours and then ran back down in one hour has been running downhill was 2.8 mph greater than
coldgirl [10]

Answer: he hiked 5.6 miles up the canyon.

Step-by-step explanation:

Let x represent his speed hiking uphill.

His speed running downhill was 2.8 mph greater than his speed hiking uphill. This means that his speed running downhill would be x + 2.8

Distance = speed × time

Kevin hiked up Lamb’s Canyon in 2 hours. This means that the distance covered by hiking uphill is 2 × x = 2x

He ran back downhill in 1 hour. This means that the distance covered by running downhill is 1 × (x + 2.8) =

x + 2.8

Since the distance uphill is the same as the distance downhill, then

2x = x + 2.8

2x - x = 2.8

x = 2.8

Therefore, the distance hiked up the canyon is

2x = 2 × 2.8 = 5.6 miles

8 0
3 years ago
Other questions:
  • A basket with 25 similar balls has a mass of 10.3 kg. The same basket with
    15·2 answers
  • there are 36 cans of beans and 48 cans of corn. the display designer wants an equal number of each vegetables in each row. what
    14·1 answer
  • Plz help me with this
    14·1 answer
  • use the rules for multiplication by powers of 10 to calculate 20 × 100. a. 200 b. 20 c. 2,000 d. 20,000
    7·2 answers
  • Can someone help me quickly please
    13·2 answers
  • Linear functions can be written with equations in the forms y=mx and y=mx+b. In which form is the linear function in the example
    12·1 answer
  • What is the perimeter, in units, of the model?
    11·1 answer
  • SOMEONE PLEASE HELP I WILL GIVE BRAIN LIEST 6TH GRADE MATH
    10·2 answers
  • Help! I’ll give brainlist!
    15·1 answer
  • Necesito la respuesta con explicación de:<br> (6+5)-16
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!