Quandaries and Queries
  

 

Name: Patricia
Who is asking: Parent
Level of the question: Elementary

Question: explaination of how to add three addends if you use a double to add or if you use a sum of 10

8+3+2=
6+4+0=
3+3+6=
2+5+4=

thank you
 

 

Hi Patricia,

We're not sure what "double to add" means.

8+3+2

  • Sum of 10: can get 10 with 8 and 2, so the answer is 13

6+4+0

  • Sum of 10: can get 10 with 6 and 4, so the answer is 10
    OR
    4 and 4 is 8 and 2 more is 10

3+3+6

  • Sum of 10: 6 and 3 is 9, one more (from 3) is 10, so answer is 12

2+5+4

  • Sum of 10: 5 and 4 is 9, one more (from 2) is 10, so answer is 11

Paul and Penny