 Hi and welcome to the session. Let us discuss the following question, question size. Find the values of the letters in the following and give reasons for the steps involved. Let us now move on to the solution. First of all, we will rewrite the given puzzle that is 12a plus 6ab gives a09. Now we need to find value of two letters that is a and b. Now study the addition in tenths column. Clearly you can see one digit of 2 plus a is 0. Now you know that this is possible only if a is equal to 8. Now we can write since one digit of 2 plus a is 0, it must be that a is equal to 8 in tenths column. Now for a equal to 8, 12a is 128 and a09 is 809. Now we know that a09 represents the sum of two numbers and 12a represents one of the number. Now if we subtract 128 from 809 we get the other number. Now on subtracting 128 from 809 we get 681 and this 681 represents the number 6ab. So we get the required value of b is 1. Now we can solve the puzzle as 128 plus 681 gives 809 and we get value of a is equal to 8 and value of b is equal to 1. So this is our required answer. This completes the session. Hope you understood the solution. Take care and bye for now.