What is 457 minus 392?

• A. 60
• B. 67
• C. 70
• D. 65

Answer: (D)

Subtracting with regrouping in place value. When you can’t subtract in a column, borrow 1 from the column to the left and add 10 to the current column.

For 457 minus 392: units place is 7 minus 2 equals 5. In the tens place you have 5 minus 9, which isn’t possible, so borrow 1 from the hundreds: the 4 hundreds becomes 3, and the tens place becomes 15. Then 15 minus 9 equals 6. In the hundreds place, 3 minus 3 equals 0. Put the digits together and drop the leading zero: the difference is 65.