Addition & Substraction Tricks

Master Addition & Substraction Faster

Discover quick calculation methods and smart shortcuts that make addition and subtraction easier, faster, and more accurate. 

Trick 1: Break Numbers into Parts

Split a number into tens and units to make addition easier.

Example:
48 + 27
= 48 + 20 + 7
= 68 + 7
= 75

Trick 2: Make a Number Round

Add to a nearby multiple of 10 and then adjust.

Example:
49 + 36
= 50 + 36 − 1
= 86 − 1
= 85

Trick 3: Add from Left to Right

Instead of starting from the units, add larger place values first.

Example:
347 + 256
= 300 + 200 + 40 + 50 + 7 + 6
= 500 + 90 + 13
= 603

Quick Tip: This is often easier for mental calculation than traditional column addition.

Trick 4: Add by Compensation

Round one number up, then subtract the amount you added.

Example:
398 + 247
= 400 + 247 − 2
= 647 − 2
= 645

Trick 5: Subtract by Counting Up

When subtracting a number close to the target, count upward from the smaller number.

Example:
1000 − 997

997 → 1000 = 3

So:

1000 − 997 = 3

This is especially useful when the numbers are very close.

Trick 6: Subtract by Rounding

Round the number being subtracted, then compensate.

Example:
83 − 29
= 83 − 30 + 1
= 53 + 1
= 54

Trick 7: Subtract in Parts

Break the number you are subtracting into manageable parts.

Example:
754 − 326
= 754 − 300 − 20 − 6
= 454 − 20 − 6
= 434 − 6
= 428

Trick 8: Add and Subtract the Same Number

Choose a convenient number to simplify the calculation.

Example:
998 + 467

Add 2 to 998 and subtract 2 from 467:

998 + 467
= 1000 + 465
= 1465

This is a powerful mental-math technique for numbers close to multiples of 10, 100, or 1000.

Trick 9: Use Complements to 100

Find how much a number needs to reach 100, then use the complement.

Example:
97 + 68

97 needs 3 to reach 100.

Take 3 from 68:

97 + 68
= 100 + 65
= 165