My number has 2 hundred. The tens digit is 9 more than the ones digit. Find the number.
We will use the concept of a number system in order to find the required number.
Answer: The required number is 290.
Let us see how we will use the concept of the number system in order to find the required number.
It is given that the number has two hundred. Hence, the number on the hundreds place is 2.
Also, it is given that the tens place digit is 9 more than the units place digit.
Therefore, one's place digit has to be zero as the ten's place has to lie between 0-9.
This makes the ten's place digit 9