Question

the ten's digit of a two digit number is twice the unit's digit. The sum of the number and its unit's digit is 66. find the number

Answer 1

The number is 63

Step-by-step explanation:

Let the ten's digit of the two digit number be x and the one's digit be y.

Then the number is 10 x + y

Any two can be written in the form of 10 x + y

Example 43 = 10×4 + 3

since it is given that the ten's digit of the number is twice the unit's digit

then x = 2 y

so the number becomes 10 × 2 y + y =20 y + y = 21 y

ATP

21 y + y = 66

⇒22 y = 66

⇒y = $\frac{66}{22}$

⇒y = 3

Therefore the number is 21 y = 21× 3 =63

Answer 2

Answer:

Number is 63.

Step-by-step explanation:

Let the Ten's digit be x.

And the Unit's digit be y.

So, the number formed will be 10x+y.

The Ten's digit is twice the Unit digit. So,

10×2y+y

= 21y.

Number=

$21y + y = 66 \\ 22y = 66 \\ y = 3$

Number formed= 21y

So, 21×3= 63