How many three digit numbers have a digital root =8 with an order 1?
option (b)
question is A+B+C=8, where a>0. Question changes to A+B+C=7. Using 1-0 method, Answer is based on the arrangement of 7 zeroes and 2 ones =9C2=36
How many three digit numbers are there with distinct digit with each digit odd?
How many three digit numbers have exactly three factors?