Subtraction of 5, 6 and 7 digit numbers (without regrouping)
In the previous class, we have learnt the subtraction of two numbers up to four digits. In this class, we will learn how to subtract 5, 6 and 7-digit numbers.
Subtraction without regrouping : Arrange the numbers being subtracted in columns based on their place value (ones, tens, hundreds, etc.) and then subtract each column separately.
Example 1: Subtract the following:
Step 1 : subtract ones, 8 ones – 1 one = 7 ones.
Step 2 : subtract tens, 5 tens – 2 tens = 3 tens.
Step 3 : subtract hundreds, 3 hundreds – 3 hundreds = 0 hundreds.
Step 4 : subtract thousands, 6 thousands – 3 thousands = 3 thousands.
Step 5 : subtract ten thousands, 7 ten thousand – 1 ten thousand = 6 ten thousands.
Step 6 : subtract lakhs, 4 lakhs – 3 lakhs = 1 lakh. Step 7 : subtract ten lakhs, 6 ten lakhs – 2 ten lakhs = 4 ten lakhs.
Example 2:
Step 1 : subtract ones, 5 ones – 1 one = 4 ones.
Step 2 : subtract tens, 6 tens – 3 tens = 3 tens.
Step 3 : subtract hundreds, 8 hundreds – 1 hundred = 7 hundreds.
Step 4 : subtract thousands, 3 thousands – 3 thousands = 0 thousands.
Step 5 : subtract ten thousands, 7 ten thousands – 2 ten thousands = 5 ten thousands.
Step 6 : subtract lakhs, 5 lakhs – 2 lakhs = 3 lakhs
Example 3:
Step 1 : subtract ones, 6 ones – 1 one = 5 ones.
Step 2 : subtract tens, 5 tens – 4 tens = 1 ten.
Step 3 : subtract hundreds, 4 hundreds – 4 hundreds = 0 hundreds.
Step 4 : subtract thousands, 3 thousands – 1 thousand = 2 thousands.
Step 5 : subtract ten thousands, 7 ten thousands – 2 ten thousands = 5 ten thousands.
Subtraction of 5, 6 and 7 digit numbers (with regrouping)
Subtraction without regrouping : First, separate the numbers being subtracted into columns based on their place value (ones, tens, hundreds, etc.). Then, subtract each column separately, starting with the ones column and moving left. If the number in the column being subtracted from is smaller than the number being subtracted, you’ll need to “borrow” from the column to the left.
Example 1:
Step 1 : subtract ones, 8 ones – 2 ones = 6 ones.
Step 2 : subtract tens, 4 tens – 5 tens is not possible, borrow 1 hundred from hundreds and then subtract, 14 tens – 5 tens = 9 tens.
Step 3 : subtract hundreds, 4 hundreds – 2 hundreds = 2 hundreds.
Step 4 : subtract thousands, 6 thousands – 3 thousands = 3 thousands.
Step 5 : subtract ten thousands, 10 thousands - 70 thousands is not possible, borrow 1 lakh from lakhs and then subtract, 11 ten thousands – 7 ten thousands = 4 ten thousands.
Step 6 : subtract lakhs, 3 lakhs – 4 lakhs is not possible, borrow a ten lakh and then subtract so 12 lakhs - 4 lakhs = 8 lakhs.
Step 7 : subtract ten lakhs, 5 ten lakhs – 2 ten lakhs = 3 lakhs.
Mental Subtraction
Let’s find the difference between 44 and 28
Count on from 28 to 30. Hold the 2 in your head. 30 to 44 is 10 + 4 = 14.
Add the 2 in 14.14 + 2 = 16 is the answer.
Find the difference between 130 and 50.
Count from 5 to 13. 13 - 5 = 8. So, 130 — 50 =80
Properties of Subtraction
Property 1: If 0 is subtracted from any number, we get the number itself as the difference.
Example: 34,142 - 0 = 34,142 and 5,88,776 - 0 = 5,88,776
Property 2: If a number is subtracted from itself, we get 0 as the difference.
Example: 34,142 - 34,142 = 0