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Each problem sum can be answered using different methods. Explore the methods and find one which makes the most sense to your child. You can also combine methods.
Susan has 3 blueberry muffins and 4 chocolate chip cookies. How many muffins and cookies does Susan have altogether?
Answer: 7
3 + 4 = 7
Draw out the number of muffins and cookies. Count them.
I have some pencils. I gave my little brother 2 of my pencils. I have 4 pencils left. How many pencils did I have at first?
Answer: 6
To find the number of pencils at first, imagine that we take the 2 pencils back from the little brother and add it to the number of pencils left:
4 + 2 = 6
We start at the 4 pencils left.
4 + 2 = 6
4 + 2 = 6
Sally has 8 books. John has 3 more books than Sally. How many books do both children have altogether?
Answer: 19
This question has a few steps. It is advisable to write statements to keep track of our working.
Sally's books: 8
John's books: 8 + 3 = 11
Altogether: 8 + 11 = 19
(Both)
We draw 8 books for Sally.
John has 3 more books than Sally. Draw the same number of books as Sally, then draw 3 more books.
Now count all the books.
From the model:
Sally's books: 8
John's books: 8 + 3 = 11
Total = 8 + 11
= 19
A book costs $12. A toy car is $7 cheaper than the book. How much money do I need to buy the book and toy car?
Answer: $17
This question has a few steps. It is advisable to write statements to keep track of our working. We don't need to write the $ sign in our working.
Book: 12
Toy Car: 12 - 7 = 5
Altogether: 12 + 5 = 17
(Both)
The numbers in this question are too big for us to draw pictures so we use tally marks instead.
From the model, we can see that:
Book: 12
Toy car: 12 - 7 = 5
Total = 12 + 5
= 17
Micky is 4 years younger than Tom. Their ages combined is 18. How old is Micky?
Answer: 7
First we draw models. Since Micky is 4 years younger than Tom, the difference in their ages is 4.
Now we list the combinations of pairs of numbers that total 18. (We don't have to make a complete list.)
Now we find the difference between the numbers listed. The pair we want must have a difference of 4.
Difference
Since Micky is younger, his age is the smaller number, which is 7.
Sam bought some fruits. There are 5 more apples than oranges. There 7 fewer pears than apples. If there are 6 pears, how many fruits did Sam buy altogether?
Answer: 27
This question is complicated so we have to solve it a small part at a time. We start with the number we know, which is the number of pears.
Pears: 6
Apples: Since there are fewer pears than apples, the number of apples must be bigger than the number of pears.
6 + 7 = 13
Oranges: Since there are more apples than oranges, the number of oranges must be smaller than the number of apples.
13 - 5 = 8
Altogether: 6 + 13 + 8 = 27
Now do the working:
Pears: 6
Apples: 6 + 7 = 13
Oranges: 13 - 5 = 8
Total: 6 + 13 + 8 = 27
Do the working:
Pears: 6
Apples: 6 + 7 = 13
Oranges: 13 - 5 = 8
Total: 6 + 13 + 8 = 27
Please let us know if you have any questions or comments on these explanantions.