50 likes | 203 Views
Adding and Subtracting. Review of Adding. Line up each column with the same value in the number below: 457 8 (8 is in the ones column) +654 3 (3 is in the one column). Adding Whole Numbers. Once the columns are lined up, add the numbers
E N D
Review of Adding • Line up each column with the same value in the number below: 4578 (8 is in the ones column) +6543 (3 is in the one column)
Adding Whole Numbers • Once the columns are lined up, add the numbers • Remember to carry to the next column if the sum is more than 9 The extra numbers at the top are carried over 1 1 4 578 +6 343 • 8 + 3 =11 so the number in the ones column goes below, the number in the tens column goes above the next column 9 10 2 1 • 7+4+1=12 so the 2 goes on the bottom and the one goes above • 5+3+1=9 so the 9 goes below and 4+6=10 • Since there is no more to add, both numbers go below
Review of Subtracting • Line up each column with the same value in the number below: 6 372 -3 548 2 is in the ones column 8 is in the ones column
Subtracting Whole Numbers • Once the numbers are lined up, subtract the numbers • Remember to borrow from the next column if the bottom number is too small (the digit being borrowed gets smaller by one • You can’t subtract 8 from 2 so we borrow a ten to make it 12-8 • The 7 in the tens becomes 5 1 1 6 6 372 -3 548 \ \ • 6-4=2 • You can’t subtract 5 from 3 so we borrow a ten to make it 13-5 • The 6 in the thousands becomes a 5 2 8 2 4 • 13-5=8 • 5-3=2