AB + CD = XXX, where AB and CD are two-digit numbers and XXX is a three digit number; A, B, C, and D...
AB + CD = XXX, where AB and CD are two-digit numbers and XXX is a three digit number; A, B, C, and D are distinct positive integers. In the addition problem above, what is the value of C?
Answer/Solution
9
Steps/Work
AB and CD are two digit integers, their sum can give us only one three digit integer of a kind of XXX it's 111.
So, A=1. 1B+CD=111
Now, C can not be less than 9, because no to digit integer with first digit 1 (mean that it's<20) can be added to two digit integer less than 90 to have the sum 111 (if CD<90 meaning C<9 CD+1B<111) --> C=9
Answer: D.
So, A=1. 1B+CD=111
Now, C can not be less than 9, because no to digit integer with first digit 1 (mean that it's<20) can be added to two digit integer less than 90 to have the sum 111 (if CD<90 meaning C<9 CD+1B<111) --> C=9
Answer: D.