Answer:
9*364 - 9*125 - 9*39 = 1,800
Step-by-step explanation:
Mental Calculation
If we detect known patterns in the calculations, we could easily give their results without the use of calculators.
We are given the expression to evaluate:
9*364 - 9*125 - 9*39
The first thing to note is the 9 is a common factor of all terms, thus we take it out:
9*(364 - 125 - 39)
The negative numbers can be easily added
125
+ 39
------------
164
Now our expression is much easier:
9*(364 - 164)
The subtraction of 364-164 is 200, thus the result of the operations is:
9*200. We only need to recall 9*2=18 and add two zeros to get 1,800, thus:
9*364 - 9*125 - 9*39 = 1,800
