Basic Subtraction {App Users/Mobile Users}

The opposite of addition is subtraction.

When you subtract, you are taking away something.

Ex) If you have 10 apples and Bob takes away 2, then you will have 8 apples left.

You: 🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎

Bob: 👉🍎🍎

Your Final Amount: 🍎🍎🍎🍎🍎🍎🍎🍎

➥This means the 'taking away' part is the subtraction symbol, ➖

Of course like addition you can write out a subtraction problem as a string of numbers or have them written in a table.

String Method:

Writing a subtraction equation into a string of numbers can be great when are able to do simple subtraction perfectly and solve things like, 22 ➖ 14, quickly. The method of using a string is better for those who are able to mentally do calculations in their head. To utilize the most efficient way of solving a string of numbers, you should always cancel numbers that equal to one another and group up numbers so they cancel out with other numbers.

Ex)

19 ➖ 2 ➖ 4 ➖ 7 ➖ 5 ➖ 1

You can solve this through the simple way:

|19 ➖ 2 = 17 | 17 ➖ 4 = 13 | 13 ➖ 7 = 6 |

|6 ➖ 5 = 1 | 1 ➖ 1 = 0

Or you can group up

⥛[2 ➖ 4 ➖ 7 ➖ 5 ➖ 1]

and instead of subtracting them you add them:

= 19 ➖ (2 + 4 + 7 + 5 + 1)

= 19 ➖ (19)

= 0

Note: When you group up numbers and add them, make sure you do not group the first number because the first number will always be the one you subtract your grouped number to.

Table Method:

Writing a subtraction equation into a table is similar to addition but it gets a bit more complicated when you end up subtracting a big digit to a smaller digit. Let's begin!

Ex) ₁ ₉ ₁₀ ₁₃

` 52013 ` 5 2̸ 0̸ 1̸ 3̸

➖ 16238 ⇒ ➖ 1 1 2 3 8

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯ ⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯

` 4 0 7 7 5

Ans: 40775

Explanation:

When you subtract a smaller number by a larger number such as the, 3 ➖ 8, you will need to bring a 10 over from the number to the left of it. The reason why you bring 10 over is because when you move to the left the numbers are getting bigger by multiples of 10. The tenths place (all the way on the right) is next to the hundreds place (to the left) which is 10 times as much as the tenths place [10 × 10 = 100]. However when you bring over the ten you have to subtract 1 from the number you got the 10 from. Which is why the 1 on the left of the 3 is slashed through and similarly for the others.

Note:

If the number is bigger than the number it is being subtracted by, the method does not change how you subtract it. For example the; 5 ➖ 1 is subtracted normally, so that is why there is a 4. Also you subtract it by column to column starting from the left and make sure to keep your numbers in the columns aligned so that you do not make simple mistakes from it.

Subtraction can be tough but practice makes perfect!