how could thinking about 90 tens help you find 1,901 - 297 ?

To understand how thinking about 90 tens can help you find the difference between 1,901 and 297, let's break down the process step by step:

1. Recognize the number pattern: Notice that 90 tens is equal to 900. So, we can rewrite the problem like this: 1,901 - 297 is equal to 1,901 - 900 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10 - 10.

2. Simplify the calculation: From the above representation, we can observe that subtracting 900 from 1,901 gives us 1,001. Then, subtracting 10 (90 times) from 1,001 gives us 101.

Therefore, the difference between 1,901 and 297 is 101.

By breaking down the numbers into their place values and using the concept of regrouping or borrowing from higher place values (in this case, borrowing from the hundreds place), we can simplify the subtraction process and better understand the relationship between the numbers.