Question

The sum of digit of a 2 digit number is 10. The tens digit is 4 times the ones digit. Find the number.

Answer 1

Answer:

Step-by-step explanation:

hey here is your answer

Let the digit in the ten’s place be denoted by x and the digit in the unit’s place be denoted by y. The number itself is 10*x + y (for e.g. if the number is 45, 45 = 10*4 + 5).

Now we know that y = 4*x or

y - 4*x = 0 → Let’s call this Equation 1.

We also know that x+y = 10 → Let's call this Equation 2.

If we subtract Equation 1 from Equation 2, we get:

(x + y) - (y -4*x) = 10 - 0

or x + y - y -(-4*x) = 10

or

5*x = 10 or x = 2

and thus y = 4*x = 8.