Question

The units digit is double than tens digit of a two digit number. If you interchange the digits and add the resulting number to the original number you get 66. What is the original number?​

Answer 1

Answer:

24

Step-by-step explanation:

4 is the double of 2 (2×2=4). If the digits are interchanged, the number is 42.

42+24=66. Hence, 24 is the answer.

Hope it helps.

Answer 2

Answer:

Let tens digit be x.

Unit's digit = 2x

Original number = 10x + 2x = 12x

Reversed number = 20x + x = 21x

According to the question

21x + 12x = 66

33x = 66

x = \frac{66}{33}x=

33

66

x = 2

Original number = 12x = 12 * 2 = 24

Therefore, original number is 24.