How do you add 4 two-digit numbers ?

Let’s review Decomposing is taking apart a number Let’s review Decomposing is taking apart a number. 5 can be decompose into 4 ones and 1 one. 23 can be decomposed into 20 and 3.

A common misunderstanding is that in addition the order of the addends changes the sum. That is incorrect. The order of the addends does not change the sum. 10+7 = 17 and 7 +10 = 17

The farmer grew tomatoes The farmer grew tomatoes. On Monday he harvested 26 tomatoes, on Tuesday he harvested 35 tomatoes, Wednesday he harvested 14 tomatoes and Thursday he harvested 23 tomatoes. How many tomatoes did he harvest in all? What is this question asking? The farmer picked 26 then 35 then 14 and lastly 23 tomatoes. We will need to add to find out how many tomatoes he picked in all.

This is an addition example that has 4 addends: 26,35,14 and 23 This is an addition example that has 4 addends: 26,35,14 and 23. One way we can decompose in order to add is to decompose the tens and the ones. First we will decompose the tens we will decompose the 20 from the 26; the 30 from 35 the 10 from the 14 and the 20 from the 23. we can add 20+30+10+20 which equals 80. Then we can decompose the ones; the 6 from the 26 the 5 from the 35the 4 from the 14 and the 3 from the 23. We can then add the ones. When I look at 6+5+4+3. I automatically see the 6+4 which equals 10. We then add the 5 + 3which equals 8 . We can then add the 10 + 8 = 18. We can now add the tens which equal 80 and the ones which equals 18, the total sum is 98. So the sum of 26+35+14+23 is 98.

The next week the farmer picked 33 tomatoes On Monday on Tuesday he picked 24 tomatoes, Wednesday he picked 17 tomatoes and Thursday he harvested 12 tomatoes. How many tomatoes did he harvest in all? We need to add the 33, 24, 17 and 12 tomatoes to find out how many the farmer picked.

This is an addition example that has 4 addends: 33,24,17 and 12 This is an addition example that has 4 addends: 33,24,17 and 12. One way we can decompose in order to add to decompose the tens and the ones. First we will decompose the tens we will decompose the 30 from the 33; the 20 from 24 the 10 from the 17 and the 10 from the 12. we can add 30+20+10+10 which equals 70. Then we can decompose the ones; the 3 from the 33 the 4 from the 24 the 7 from the 17 and the 2 from the 12. We can then add the ones. When I look at 6+5+4+3. I automatically see the 3+7 which equals 10. We then add the 4 + 2 which equals 6 . We can then add the 10 + 6 = 16. We can now add the tens which equal 70 and the ones which equals 16, the total sum is 86. So the sum of 33+24+17+12 = 86.