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Sunday, November 13, 2011

Subtraction 1: May I Borrow Some of Your Numbers?

OK, so now you know everything you need to know about addition, but now we're headed on to subtraction. Subtraction is when you take away numbers instead of adding numbers. Let's say we have 10, and we subtract 7. Like addition, we start with the unit column. Zero - seven. Because we cannot take 7 from zero, we need to borrow from the one in the ten column. We would turn that one into whatever number is one less than the number. In this case, that number would be zero. We put the one behind the zero in the unit column to make that zero a ten. Now, what is 10 - 7? If you need help, here's how to do it: with subtraction, we need to count down seven numbers from 10, because we are taking away numbers. Like addition, we don't count 10. OK, let's start counting down. 9, 8, 7, 6, 5, 4, 3, STOP!! We've now taken away 7 numbers from 10. What was the LAST number we counted? If you said 3, you're right!! If not, you might want to watch some videos on www.khanacademy.org or you could read this lesson over again and you might understand it. If you now understand it, awesome!! You're all on a great path!! Addition and subtraction are the first out of all arithmetic you'll learn. In time you'll be masters at these two subjects. Until the next lesson, see ya!!

Addition 2: Landing On Solid Ground

Now that we've learned how to add 2 units together, now let's try adding 2 tens together. We start with the one column and work our way to the final colomn. Let's say we have 17, and we add 6. We start at the one colomn, 7 + 6. What is 7+6? If 6+6 is 12, then 7+6 must be 13! Here comes the tricky part. Because the number is bigger than 9, we need to carry the 1 over to the tens colomn. Now, what was the unit (one) in the answer? If you said 3, you are correct! So we put 3 in the ones colomn. Now for the tens colomn. You may be temped to say, "well, one plus nothing = 1, so I should put a one there," WRONG!! Don't forget get about that one we carried. If one + nothing = one, then what should we do with the carried number (1)? We add it to the sum of the tens (the answer in the tens colomn)! So now we have 1 + 1. What is the answer? 2!! So the sum (total) is 23!! If you guessed that, Hurray!! If not, read the lesson again or go to www.khanacademy.org and do their exercices.

Saturday, November 12, 2011

Addition 1: The First Step

Addition is when we add 2 numbers together to make a new number. Let's say we have 2, and we add 3. We start out by counting up from 2. When we've counted 3 numbers, we stop. But we don't count the number we first started with. In this case, that number is 2. Now we count tnree numbers from 2. 3, 4, 5, STOP!! We've counted 3 numbers. What is the last number we stopped at? If you said 5, you're right! If you thought otherwise, you should go to www.khanacademy.org and watch their videos on addition. Or, you can just keep reading this lesson. Now on to harder problems. What is 6 + 6? If you know the answer already, great! But for those who still need help, just keep on reading this. OK, we'll do the same thing that we did with our first problem. We'll start from 6 and count six numbers until we reach our answer. But, we won't count our first number. Now, let's count. 7, 8, 9, 10, 11, 12, STOP!! We've now counted 6 numbers. The last number we counted will be our answer. If you said 12, you're right! If you didn't think that, then you should really go to Khan Academy. There is a link above. See ya later!