The 18 times table can be daunting for students, but with the right tips and strategies, they can be learned quickly.
In this article, I provide a number of different methods that can help make learning 18 times tables easier.
I also provide explanations and examples so that you can see how these techniques work and how you can apply mental math strategies. Let’s get started!
18 Times Table Multiplication Chart
Here is a list of the 18 times tables for the first 12 multiples.
18 x 1 = 18
18 x 2 = 36
18 x 3 = 54
18 x 4 = 72
18 x 5 = 90
18 x 6 = 108
18 x 7 = 126
18 x 8 = 144
18 x 9 = 162
18 x 10 = 180
18 x 11 = 198
18 x 12 = 216
Save this image for a handy multiplication table of 18.
5 Different Strategies for learning the 18 times tables
Rather than having to memorize the 18 times tables like the 0-12 multiplication tables, I think it is more beneficial to learn strategies to help you make a list of the first 18 multiples or calculate a multiple of 18.
Here are the best 4 strategies for learning the 18 times tables.
Digits pattern
This is a good trick if you just want to list the multiple of 18. If you want to calculate a multiple of 18 without listing all of them other strategies are better.
Notice the units digits follows the pattern 8, 6, 4, 2, 0 and repeats.
I have highlighted this in red.
Then the first 5 tens digit are the odd numbers 1, 3, 5, 7, 9. This is shown in blue.
This is followed by 5 even numbers 10, 12, 14, 16, 18 shown in purple.
And then continues as 5 odd numbers 19, 21, 23, 25, 27.
Add the 10 and 8 times tables (The distributive property)
If you know your 8 and 10 times tables then you can add these together to find the 18 times tables because 8 +10 = 18.
This is an extension of the distributive property that is a good mental math strategy to use.
Algebraically the distributive property looks like this:
Applying this to the 18 times tables looks like this:
Double the 9 times tables.
Using the fact that 9 x 2 = 18, if you know the 9 times tables, then you can double your answers to find the 18 times tables.
Subtract the 2 times tables from the 20 times tables (The commutative law)
Using the fact that 20-2 = 18, we can use the distributive property again.
Algebraically this is what we are doing:
So you can calculate any multiple of 18 by multiplying by 20 and 2 and finding the difference.
Double and Halve
This is one of my favorite multiplication strategies. It works well because 18 is an even number so you can halve it and double the number you a multiplying by.
For example if you want to find 18 x 3,
Tips to Learn Them Quickly
Practice, practice practice! This is the best way to learn any math skill.
- List the multiples using the digits pattern strategy then practice other multiples using the other strategies.
- Roll a die or pick a card from a deck of cards and multiply this number by 18.
- Try the examples below.
You may find you prefer different strategies for different multiples of 18 and that is OK.
Examples of How to Use These Techniques
Let’s try a few examples to see how we can apply these strategies.
Example 1: Whitney earns $18 per hour. How much does she earn for working a 5 hour shift?
Solution:
Using the doubling and halving strategy 18 x 5 = 9 x 10 = 90
So Whitney earns $90 for the shift.
Example 2: Brian cycles 18 miles per hour. How many miles does he cycle over a week if he cycles for 3 hours every Saturday and 1 hour every weekday morning?
Solution:
1 hour every weekday morning = 5 hours in total
5 hours + 3 hours = 8 hours / week of cycling.
Distance = speed x time
= 18 miles/ hr x 8 hr
Using the strategy of doubling the 9 times tables,
Example 3: A truck has 18 wheels. If there are 7 nuts on each wheel, how many nuts are needed to be serviced?
Solution:
We need to find 18 x 7, so using the 8 and 10 times tables:
Final thoughts on the 18 times table
While it’s important to know your 18 times tables, you don’t need to memorize them by heart. You can use different multiplication strategies to calculate any multiple of 18.
Practice these strategies so they become automatic for you. With a little bit of practice, you’ll be able to multiply any number by eighteen.
