2.NBT.8 — Mentally Subtract 10 or 100
Practice mentally subtracting 10 or 100 from three-digit numbers between 100 and 900 to build strong number sense and place value understanding.
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Three different problem sets — same skill, same layout, fresh numbers.
Preview — Set A
Subtract 10 or 100 from each number in your head and write the answer.
- 1.200 - 10 =
- 2.350 - 100 =
- 3.475 - 10 =
- 4.630 - 100 =
- 5.812 - 10 =
- 6.740 - 100 =
- 7.563 - 10 =
- 8.900 - 100 =
- 9.128 - 10 =
- 10.500 - 100 =
- 11.687 - 10 =
- 12.420 - 100 =
- 13.315 - 10 =
- 14.750 - 100 =
- 15.241 - 10 =
- 16.860 - 100 =
- 17.193 - 10 =
- 18.507 - 100 =
- 19.724 - 10 =
- 20.600 - 100 =
What this worksheet covers
There are twenty place value problems here — one page to work, one page of answers to check against — and Sets B and C repeat the layout with different numbers. Within that, one of the twenty column problems need regrouping and the rest do not, so the two cases are mixed rather than blocked and the numbers run as high as 900. Problems 7 and 14, for instance, are "563 - 10" and "750 - 100". Common Core 2.NBT.8 is the slot this page fills.
Skills practised
The grade 2 place value sequence covers hundreds, tens and ones, expanded form to 999, and 10 or 100 more and less; this page sits inside it. What a student is asked to do here is mentally Subtract 10 or 100. Working the page asks a student to regroup past ten rather than counting up one at a time.
About the drill format
A drill is straight practice: 20 problems of the same kind, laid out across the page with working space under each — problem 7, "563 - 10" is typical of the whole page. Repeating one question shape — which digit, what value, round to which place — is how the vocabulary of place value becomes automatic.
Set A, Set B and Set C
Set A is the sheet as it was first published on MathSheetLab, and Sets B and C were derived from it problem by problem: each number became a slot redrawn with the same shape, and every answer was recomputed exactly. Where Set A's problem 11 is "687 - 10", Set B's is "210 - 10".
How to use this worksheet
Grade 2 attention runs short, so split these twenty place value problems over two or three sittings rather than pushing through in one; a number line or counters within reach is a strategy, not a failure. Keep the key face down until all twenty problems are finished, then go through the misses together rather than only totalling the score.
One mistake to watch for
Ten more than 47 is found by counting on by ones. On this grade 2 drill, problem 14 ("750 - 100") is the kind of item where it shows.
The tens digit has not yet been seen as a thing that can be changed on its own.
Use a hundreds chart and trace the move straight down one row; the ones digit stays put and the student can see it.
Other grade 2 place value formats
The same skill in the other formats available at this grade.
- Timed Drill — Grade 2 Place Value Timed Drill, 60 problems
- Missing Number — Grade 2 Place Value Missing Number, 24 problems
- Mixed Review — Grade 2 Place Value Mixed Review, 24 problems
- Word Problems — Grade 2 Place Value Word Problems, 8 problems
A step either side
The same format one grade down and one grade up — the easier sheet is often the faster fix when this one is not landing.
- 1.NBT.5 — 10 More or 10 Less Practice — grade 1, 20 problems
- Grade 3 Place Value Drill — grade 3, 30 problems
Drill sheets in other grade 2 topics
No paywall and no account — download any set of this grade 2 place value drill, and the answers for all twenty problems are in the matching key.