Multiplication Tricks That Make Big Numbers Feel Small
Multiplication tricks are shortcuts that turn big looking problems into quick, friendly steps. Here are several you can use straight away, each with an example.
Multiply by 10, 100 and 1000
Shift the digits left and fill with zeros. 34 times 10 is 340, and 34 times 100 is 3400. Decimals work the same way: 3.4 times 10 is 34.
Multiply by 5
Multiply by 10, then halve the result. For 5 times 18, take 10 times 18 equals 180, then half of that is 90.
Multiply by 9
Multiply by 10, then subtract the number once. For 9 times 7, take 70 and subtract 7 to reach 63. For 9 times 15, take 150 and subtract 15 to reach 135.
Multiply by 11 for two digit numbers
Add the two digits and place the total between them. For 11 times 23, add 2 and 3 to get 5, so the answer is 253. When the digits total 10 or more, carry the 1 into the first digit: for 11 times 78, 7 plus 8 is 15, so the answer is 858.
Multiply by 4 and 8
Double, then double again for 4. For 4 times 17, double to get 34, then double to get 68. For 8, double three times: 8 times 6 means 12, 24, 48.
Break a number into tens and ones
This works for almost any problem. For 7 times 16, split 16 into 10 and 6. Then 7 times 10 is 70 and 7 times 6 is 42, and 70 plus 42 gives 112.
Square numbers ending in 5
Take the tens digit, multiply it by the next number up, and attach 25. For 35 squared, 3 times 4 is 12, so the answer is 1225. For 65 squared, 6 times 7 is 42, so the answer is 4225.
Round and adjust
Choose a friendly nearby number, calculate, then correct. For 19 times 6, think 20 times 6 equals 120, then subtract 6 to reach 114. This approach shines whenever a number sits close to a multiple of ten.
Check answers with estimation
A quick estimate keeps you on track. For 48 times 6, round 48 to 50, so the answer should sit near 300. The true answer, 288, is close, which confirms the result looks right.
Combine tricks for bigger problems
Tricks work well as a team. For 12 times 15, split 12 into 10 and 2: 10 times 15 is 150 and 2 times 15 is 30, giving 180. For 25 times 8, double and halve: 25 times 8 equals 50 times 4 equals 100 times 2, which is 200. Choosing the trick that fits the numbers is a skill in itself, and it grows every time you practise.
Practise one trick a day
Pick a single trick each day and use it on five problems from around you, such as prices, page numbers or the number plates you pass. By the end of the week you will own a full toolkit.
Put the tricks to work
Tricks become second nature through repetition. Multiplication Master gives you a playful place to do that: each level presents an equation such as 6 × 7 = 42 on a tap the numbers board. Easy levels use small ranges to build speed, timed three minute levels reward quick thinking, and your score earns stars. Try the splitting and rounding ideas above while you play, and see how much faster your answers arrive.
Ready to test your new skills? Play Multiplication Master free and enjoy a few quick rounds.