Advertisement Remove all ads

The digits of a two-digit number differ by 3. If the digits are interchanged, and the resulting number is added to the original number, we get 143. What can be the original number? - Mathematics

Sum
The digits of a two-digit number differ by 3. If the digits are interchanged, and the resulting number is added to the original number, we get 143. What can be the original number?
Advertisement Remove all ads

Solution

Let us take the two-digit number such that the digit in the units place is b.
The digit in the tens place differs from b by 3. 
Let us take it as b + 3.
So, the two-digit number is 10(b + 3) + b = 10b + 30 + b = 11b + 30.
With interchange of digits, the resulting two-digit number will be 10b + (b + 3) = 11b + 3.
If we add these two two-digit numbers, their sum is (11b + 30) + (11b + 3) = 11b + 11b + 30 + 3 = 22b + 33
It is given that the sum is 143.
Therefore, 22b + 33 = 143.
or 22b = 143 - 33
or 22b = 110
or b = `110/22`
or b = 5
The units digit is 5 and therefore the tens digit is 5 + 3 which is 8. The number is 85.
  Is there an error in this question or solution?
Advertisement Remove all ads
Advertisement Remove all ads
Share
Notifications

View all notifications


      Forgot password?
View in app×