Loading…
Example 1.35 from Prealgebra, 1.3 Subtract Whole Numbers
Subtract Whole Numbers: example 1.35
Subtract and then check by adding:
Work it out on paper first. Then open the solution one step at a time, and stop as soon as you can finish on your own.
Solution
Write the numbers so each place values line up vertically. Subtract the ones. Since we cannot subtract 9 from 2, borrow 1 ten and add 10 ones to the 2 ones to make 12 ones. Write 5 above the tens place and cross out the 6. Write 12 above the ones place and cross out the 2. Now we can subtract the ones. Write 3 in the ones place in the difference. Subtract the tens. Since we cannot subtract 7 from 5, borrow 1 hundred and add 10 tens to the 5 tens to make 15 tens. Write 0 above the hundreds place and cross out the 1. Write 15 above the tens place. Now we can subtract the tens. Write 8 in the tens place in the difference. Now we can subtract the hundreds. Write 6 in the hundreds place in the difference. Subtract the thousands. There is no digit in the thousands place of the bottom number, so we imagine a 0. Write 1 in the thousands place of the difference. Check by adding. Our answer is correct.
Your turn
The book's Try It right after this example: same idea, new numbers. Only the answer is given.
Subtract and then check by adding:
How did it go?