What is an\[1,00,00,000-1=\]?

Hint: The number which is subtracted from \[1,00,00,000\] that is 1. For that we have to understand the basic principle of subtraction, that is if we subtract a unit place that is \[0-1=9\]that means we have taken the 10 and borrowed from the ten places therefore in ten places it becomes 9. If we continue up to ten lakh places then we will get the answer as 9999999.

Complete step by step answer:
In this problem the number which we need to subtract from \[1,00,00,000\] is 1.
First of all we will understand the basic principle of subtraction
If you see in this problem then there are two parts of subtraction that is minuend and subtrahend
Here, in this problem \[1,00,00,000\] is a minuend and subtrahend is 1.
Now, we come to the problem of subtracting the \[1,00,00,000\]by 1.
That means while subtraction you have to always keep in mind that in this problem we have to start subtracting from right to the left sides that is you can see that in unit place is 0 and we are subtracting from 0 then we will get \[0-1=9\]because we have borrow 1 from the ten place that means in unit place it remains as 10 and in ten place it remain as 9. Similarly we have to borrow 1 from a hundred places. That means in a hundred places it remains as 9 and so on up to ten lakh places.
Hence, we get,
\[1,00,00,000-1=9999999\]
So, our final answer is \[9999999\]

Note:
Always keep in mind while subtracting the two numbers, always start subtracting from right to the left side. If you subtract from left to right then you will get the wrong answer. Note that if you subtract \[\text{larger}\,\text{number}-\text{smaller number}\] then the sign of your answer is positive. If you subtract \[\text{smaller number}-\text{larger}\,\text{number}\] then the sign of your answer is negative because we have to consider the sign of a larger number only and not a smaller number.