Multiplying by six
This pattern is for even numbers only. The unit part of your answer is always the same as the number you are multiplying by. The tens part of the answer is always half the number of the units in the answer.
6x2 = 12 12 is 1 ten and 2 units. 2 units is the same as the number you are multiplying by. The 1 ten is half the number of units 2.
6x4 = 24
6x6 = 36
6x8 = 48
6x12 = 12 units + 6 tens = 72
6x18 = 18 units + 9 tens = 108
This pattern is for even numbers only. The unit part of your answer is always the same as the number you are multiplying by. The tens part of the answer is always half the number of the units in the answer.
6x2 = 12 12 is 1 ten and 2 units. 2 units is the same as the number you are multiplying by. The 1 ten is half the number of units 2.
6x4 = 24
6x6 = 36
6x8 = 48
6x12 = 12 units + 6 tens = 72
6x18 = 18 units + 9 tens = 108
Multiplying by nine
Between 1x9 and 10x9 the numbers in your answer should always add up to 9. Also the number of tens in your answer should always be 1 less than the number you are multiplying 9 by.
Example 1: 6 x 9 = 54. 5+4 = 9 and 5 tens is 1 less than 6.
Example 2: 3 x 9 = 27. 2+7 = 9 and 2 tens is 1 less than 3.
Between 1x9 and 10x9 the numbers in your answer should always add up to 9. Also the number of tens in your answer should always be 1 less than the number you are multiplying 9 by.
Example 1: 6 x 9 = 54. 5+4 = 9 and 5 tens is 1 less than 6.
Example 2: 3 x 9 = 27. 2+7 = 9 and 2 tens is 1 less than 3.
Multiplying large numbers by eleven
By large numbers we mean numbers from 13 to 99. There are two things (steps) we need to do to solve the answer.
Lets take 13x11 as an example.
Step 1 - add the first and second digits of the large number (in this case 13): 1 + 3 = 4
Step 2 - put the answer between the the large number's first and second digits
The answer was 4, so 4 goes between 1 and 3
The answer is 143.
In step 1 if the sum of the first and second digits is more than 9, then there are 3 steps in total.
What is 19 x 11?
Step 1 - add the first and second digits: 1 + 9 = 10
Step 2 - put the number of units (0) in the middle of the large number 109
Step 3 - add the number of tens (1) to the number on the left 1+1 = 2.
The answer is 209.
By large numbers we mean numbers from 13 to 99. There are two things (steps) we need to do to solve the answer.
Lets take 13x11 as an example.
Step 1 - add the first and second digits of the large number (in this case 13): 1 + 3 = 4
Step 2 - put the answer between the the large number's first and second digits
The answer was 4, so 4 goes between 1 and 3
The answer is 143.
In step 1 if the sum of the first and second digits is more than 9, then there are 3 steps in total.
What is 19 x 11?
Step 1 - add the first and second digits: 1 + 9 = 10
Step 2 - put the number of units (0) in the middle of the large number 109
Step 3 - add the number of tens (1) to the number on the left 1+1 = 2.
The answer is 209.