Question

In a number of two digits units digit is twice the tens digit is 36 be added to the number the digits are reversed the number is
1. 36
2. 63
3. 48
4. 84


plz help​

Answer 1

Solution: The number is in form of 10 × Ten's digit + Unit's Digit.

Given: Units Digit (One's Digit) = 2 × Ten's Digit.

If Ten's digit is x (say), then Unit's Digit = 2x.

Equation: 10x + 2x + 36 = 10(2x) + x

→ 12x + 36 = 20x + x

→ 36 = 21x - 12x

→ 36 = 9x

→ 4 = x (Ten's Digit)

Unit's Digit = 2 × 4 → 8

Number: 10 × 4 + 8 → 48 (Option 3)

Answer 2

Question :--- In a number of two digits units digit is twice the tens digit is 36 be added to the number the digits are reversed the number is ?

Solution :---

Let the tens digit be = x ,

it is said that now, unit digit is twice the tens digit.

so,

→ unit digit is = 2x .

Now, Our two digit number becomes = 10*x + 2x = 12x . ------- Equation (1)

when we interchange the digits, it becomes = 2x*10 + x = 21x . -------- Equation (2)

Now, it is given that, when we add 36 to original number , we get, reverse number ,

→ original number + 36 = Reverse number

→ Reverse number - original number = 36

Putting values from Equation (1) and equation (2) we get,

→ 21x -12x = 36

→ 9x = 36

Dividing both sides by 9,

→ x = 4

So,

→ Ten digit = x = 4

→ unit digit = 2x = 2*4 = 8 .

→ Original Number = 4*10 + 8 = 40 + 8 = 48 .

Hence, The original number is 48...