Class 8 chapter 2 ex.no. 2.4 Q.no.4

Question: 4 - One of the two digits of a two digit number is three times the other digit. If you interchange the digits of this two-digit number and add the resulting number to the original number, you get 88. What is the original number?

Solution:
Let one of the digit , which is at ones place, of a two digit number = a

Therefore, other digit of the two digit number = 3a

Therefore, number = (10 x 3a) + a = 30a + a = 31a

After interchange, the digit = 10a + 3a = 13a

Now, since sum of the original and resulting number = 88

Therefore, 31a + 13a = 88

⇒ 44 a = 88

Now, after dividing both sides by 44, we get

By substituting the value of ‘a’ in original number we get

Since, original number = 31a = 31 x 2 = 62

Thus, the number = 62 Answer- One of the

two digits of a two digit number is three

times the other digit. If you interchange the

digits of this two-digit number and add the
resulting number to the original number, you get 88. What is the original number?