Question 1139869
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The tutor @Theo has a great solution. A shortcut is to simply look for any multiple of 9 where the units digit (aka "ones digit") is 2. If a number has a 2 in this location, then that number will divide over 10 to get you a remainder of 2.


Examples of getting a remainder of 2, when we divide values over 10:
32/10 = 3 remainder 2
42/10 = 4 remainder 2
92/10 = 9 remainder 2
<font color=red>72/10 = 7 remainder 2</font>
102/10 = 10 remainder 2
1782/10 = 178 remainder 2


This is a very nice property that allows us to effectively spot the remainder without doing much math at all (some could argue there isn't any math being performed as it's simply just reading off the units digit value). The reason why this property works is because of how the base 10 system is set up. 


A number like 72 is really 70+2 = 7*10 + 2. Note how the 7*10 part indicates we basically have 7 groups of 10, and then we have an additional 2 left over. 


Or you could think of it like this {{{72/10 = (70+2)/10 = 70/10 + 2/10 = 7 + 2/10 = 7 & 2/10}}}. The 2/10 refers to a remainder of 2 out of 10. I chose not to reduce the fraction 2/10 so we can see how 72/10 leads to 7 & 2/10.
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