Hello all steemian friends, in this occasion I will share another basic tricks of arithmetic, especially for students who want to master arithmetic. This trick is named as a sum with changes.
Collecting shells on the beach is one of the activities we definitely love. You have collected a total of 29 shells this morning, and this afternoon you collect another 44 shells. How many shells you have collected? To solve this problem, we will add up to 29 + 44 using the aritmatic trick summing up with the changes.
Anytime if we add a number with a unit number 9, add 1 to number 9 (but do it just in your mind!). So, the number 29 will be 30. Then subtract 1 on the next number, so 44 will be 43. Next, add up the new numbers we've got, and we'll get the result. Let's use this trick to find out how many shells you have collected earlier!
Always remember! A multiple of 10 (like 20, 30, etc.) is always easier to add than a non-multiple of 10. This trick starts by adding 1 to the number ending with the number 9 to be a multiple of 10. If you add a number with one unit number 8, add 2, unit number 7 add 3 and so on, so that it becomes multiples of 10. Then, the second number is subtract by the number of numbers added in the first number, if in the first number plus 1 then the second number minus 1, if plus 2 then minus 2, and so on. Next add up the two new numbers. You will get immediate results. For example, 48 + 26 being (48 + 2) + (26 - 2), or 50 + 24 which result is 74.
Here is my explanation for this basic aritmatic trick, follow my post to get other arithmetic tricks, that I will explain in my next post. Hopefully, this article useful for me personally and for you all.
@saimdang