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 Beverly Mackie BellaOnline's Math Editor

Multiplication Tips - 2s, 4s, 8s

After the basic concepts of multiplication have been taught, here are some tips to learning and memorizing multiplication facts. Works well with older students.

****Remember the COMMUTATIVE PROPERTY – the order of the numbers does not change the answer. One fact learned means that two facts are actually learned.
Example: 4 x 5 = 20 and 5 x 4 = 20

2s ----------- “…seeing double” means to add the number to itself. For example,
2 X 7 = 14 is the same as 7 + 7 = 14. whenever you want to double a number, multiply by two and you are through.

4s ------- once you have mastered the 2’s. The 4’s are a breeze. How? Take the twos that you just learned and multiply the answer by 2 again. This process is the same as multiplying by four. Keep that thought in the back of your mind. Let’s calculate 4 X 6 . It can become cumbersome to think of four groups with six in each group. So, let’s try another approach.

4 x 6 =
Multiply 6 by (2 which is half of four) ------- 2 x 6 = 12
Double the answer, twelve ----------------------------- (12 + 12 = 24) or ( 12 X 2 = 24.)
Thus ----------------------------------------- 4 x 6 = 24.

Let’s try another example:
4 X 7 =
Multiply 7 by (2 which is half of four) ------- 2 x 7 = 14
Double the answer, fourteen ----------------------------- (14 + 14 = 28) or ( 14 X 2 = 28)
Thus -------------------------------------------- 4 x 7 = 28.

8s ---------Since four is half of eight, let’s use this pattern with the eight timetables.
This method requires you to know the four times tables. Instead of multiplying by 8, multiply by 4 (which is half of 8) and double the answer.

8 x 3 =
Multiply 3 by (4 which is half of 8) ------------- 4 x 3 = 12
Double the answer, 12 ------------------------- (12 + 12= 24) or (12 x 2 = 24)
Thus ----------------------------------------------- 8 x 3 = 24

Look at the products below. Do you notice any patterns?
8 x 1 = 08
8 x 2 = 16
8 x 3 = 24
8 x 4 = 32
8 x 5 = 40
8 x 6 = 48
8 x 7 = 56
8 x 8 = 64
8 x 9 = 72
8 x 10 = 80

Pattern – in the tens place: start from the top; numbers are in ascending order 0 – 4, repeats 4, and continues 5 – 8

Pattern – in the ones place: start from the bottom; skip counts by twos beginning with 0 -8; start over with zero continuing to count by twos.

Test strategy: If calculators are not allowed and you have not quite mastered the multiplication facts, write them on your test before you begin. Use the above pattern to verify they are correct. Patterns are found in several timetables. So, check out the other articles below.

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