As with addition, subtraction has only one sign: the minus sign (–). You end up with equations such as 4 – 1 = 3 and 14 – 13 = 1 and 93 – 74 = 19. When you subtract one number from another, the result is called the difference.

Steps are shown to subtract 4-digit numbers.

1. Solve: 74834 – 38915. Line up the number according to place value. In the ONES column the number to be subtracted is greater so REGROUP as 2 TENS 14 ONES. Subtract the TENS column. REGROUP to subtract the numbers in the HUNDREDS column.
2. Subtract: 39507 – 27386.

Long subtraction is a method for subtracting numbers. Long subtraction involves writing the numbers to be subtracted one underneath another, so the digits are in columns. The numbers are subtracted a column at a time. Many numbers of any length (including decimals) can be subtracted in this way.

Smaller Number – Bigger Number

1. Reverse the subtraction (to 5 − 2 = 3)
2. Find what makes it to 10 (3 + 7 = 10), then write that down as part of the answer.
3. Add 1 to the digit on the left (of the number we are subtracting).

How to add and subtract in your head

1. To add 9 to another number, add 10 and then subtract 1: 36 + 9 = 36 + 10 – 1 = 45.
2. To add 18 to another number, add 20 and then subtract 2: 48 + 18 = 48 + 20 – 2 = 66.
3. To add 97 to another number, add 100 and then subtract 3: 439 + 97 = 439 + 100 – 3 = 536.

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Here are the 5 math tricks to help improve the mental math ability of your students:

1. Make It Easy. Students can sometimes find it challenging to multiply or add big denominations.
2. Subtract By Adding.
3. Tough Multiplications Made Simple.
4. Division Tricks To Remember.
5. Solving Percentage Problems.

GENERAL RULES FOR MULTIPLICATION

1. Step 1 – Multiply the right hand side digits.
2. Step 2 – Cross-Multiplication.
3. Step 3 – Multiply the left hand side digits.
4. Step 1 –
5. Step 3 –
6. Step 4 –
7. EXAMPLE – 4325 × 3216.