3rd Grade addition problemDate: Wed, 16 Nov 94 10:48:24 PST From: Keith Averell Subject: grade 3 math Dear Mr. Math My name is Macks Colella. I want to know the answer to this problem - what is 845+904=? Thanks for your help. Macks Colella Date: Wed, 16 Nov 1994 15:42:41 -0500 (EST) From: Dr. Sydney Subject: Re: grade 3 math Dear Macks: I'm so glad you wrote to Dr. Math! It is great to hear from you. You were wondering how to add 845 and 904. I guess the way I usually approach problems like this is to write one number above the other, making sure that they line up so that the digit that is the farthest right in one number always is lined up with the digit that is farthest to the right in the other number. So in this problem, I would write: 845 +904 --- Then, add, starting with the ones digit, the digit the farthest to the right. 5+4=9, so I write: 845 +904 --- ??9 Then go to the tens digit, the digit just to the left of the ones digit and add them together. So we have: 845 +904 --- ?49 Now all that is left to do is add the hundreds digits together. The hundreds digit is just to the left of the tens digit. So, we get for our final answer: 845 +904 --- 1749 Does that make sense to you? Maybe you could try a few problems on your own? Try these, if you would like: 221+358=? 1437+8432=? 98543+34=? Write back if you have any more questions! Good luck! --Sydney |
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