Question

?1-2?=34 which digit have been replaced by ? In this sum 6,7 8,9 4,5 5,6

Answer 1

The sum is 13

Step-by-step explanation:

I am doing back substitution in this case as the difference between tow numbers is 34

As the 10 th place of second number is 2, so the tenth digit of 1 st number has to be minimum 6 so I am considering it as 61,

so the unknown number is 61-34

27

The numbers replacing ? are 6 and 7 respectively, so the sum is 13