Question

a two digit number is 3 more than 4 times the sum of its digit if 18 is added to the number its digit are reversed find the number​

Answer 1

Step-by-step explanation:

Let the digits in unit place and 2nd place are x and y

Therefore the number is=10y+x

Now codition, 1

10y+x=3+4(x+y)

10y+x=3+4x+4y

6y=3+3x

2y=1+x

2y=1+y+2 (putting x=y+2)

y=3

And codition 2

10y+x+18=10x+y

9y+18=9x

y+2=x

3+2=x

x=5

Therefore the number is =10*3+5=35

Answer 2

$\bold{\Huge{\underline{\boxed{\sf{\pink{ANSWER\::}}}}}}$

$\bold{\Large{\underline{\sf{\green{Given\::}}}}}$

A two digit number is 3 more than 4 times the sum of its digit. If 18 is added to the number its digit are reversed.

$\bold{\Large{\underline{\rm{\red{To\:find\::}}}}}$

The number.

$\bold{\Large{\underline{\sf{\orange{Explanation\::}}}}}$

Let the one's digit be R &

Let the ten's digit be M

The original number is 10M + R

• According to the question:

We have,

Two-digit number is 3 more than 4 times the sum of its digits.

→ 10M + R = 4(R + M) + 3

→ 10M + R = 4R + 4M + 3

→ 10M - 4M + R - 4R = 3

→ 6M - 3R = 3..............................(1)

&

if 18 is added from the number, the digits are reversed.

→ 10M + R + 18 = 10R + M

→ 10M - M + R - 10R = -18

→ 9M - 9R = -18

→ 9(M - R) = -18

→ M - R = $\bold{\cancel{\frac{-18}{9} }}$

→ M - R = -2...............................(2)

• Using Substitution Method:

from equation (2), we get;

⇒ M - R = -2

⇒ M = -2 + R...............................(3)

Putting the value of M in equation (1), we get;

⇒ 6(-2 + R) - 3R = 3

⇒ -12 + 6R - 3R = 3

⇒ -12 + 3R = 3

⇒ 3R = 3 +12

⇒ 3R = 15

⇒ $\bold{R\:=\:\cancel{\frac{15}{3}}}$

⇒ R = 5

Putting the value of R in equation (3), we get;

⇒ M = -2+ 5

⇒ M = 3

Thus,

The number is 10(3) + 5

The number is 30 + 5 = 35.