A two digit number is 4 times the sum of its two digits. The number that is…

2020

A two digit number is 4 times the sum of its two digits. The number that is formed by reversing its digits is 27 more than the original number. What is the number?

  1. A.

    27

  2. B.

    36

  3. C.

    42

  4. D.

    54

Attempted by 3 students.

Show answer & explanation

Correct answer: B

To find the two-digit number shown in image_8cd9fb.png, we can represent the number as 10x + y, where x is the tens digit and y is the units digit.

Step-by-Step Calculation
Condition 1: The number is 4 times the sum of its digits.

10x + y = 4(x + y)

10x + y = 4x + 4y

6x = 3y, or y = 2x

Condition 2: The reversed number (10y + x) is 27 more than the original number.

(10y + x) - (10x + y) = 27

9y - 9x = 27

y - x = 3

Solve the system of equations:

Substitute y = 2x into the second equation: 2x - x = 3

x = 3

Find y: y = 2(3) = 6

The number is 10(3) + 6 = 36.

Explore the full course: Rssb Senior Computer Instructor