What this lesson shows
581 + 72: 8 tens and 7 tens make 15 tens. Trade 10 tens for a hundred: 653.
The worked example
The lesson works this one step by step: 581 + 72. Then your kid tries one like it on paper.
The steps
- Add the ones
- Add the tens
- Trade 10 tens for a hundred
- Put the parts together
Helping at home
Add the ones, then the tens, then the hundreds. When the tens make 10 or more, trade 10 tens for a hundred. Put the parts together.
If your kid gets stuck
Ones, then tens, then hundreds.
Watch it with Lux
With Lux, this lesson is a narrated video and a printed page your kid works on. Then Lux helps with the same math on their own worksheet, one question at a time.
Standards
- Common Core 2.NBT.B.7
Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
Matches standards in 45 statesSee each state's code
- Alabama MA19.2.12a
- Alaska 2.NBT.7
- Arizona 2.NBT.B.7
- Arkansas 2.CAR.6
- California 2.NBT.B.7
- Colorado 2.NBT.B.7
- Connecticut 2.NBT.B.7
- Delaware 2.NBT.B.7
- District of Columbia 2.NBT.B.7
- Florida MA.2.NSO.2.4
- Hawaii 2.NBT.B.7
- Idaho 2.NBT.B.7.a, 2.NBT.B.7.b
- Illinois 2.NBT.B.7
- Indiana 2.CA.2
- Iowa 2.NBT.B.7
- Kansas 2.NBT.7
- Kentucky KY.2.NBT.7.a, KY.2.NBT.7.b
- Louisiana 2.NBT.B.7
- Maine 2.NBT.B.7
- Maryland 2.NOS.C.9.a, 2.NOS.C.9.b, 2.NOS.C.9.c, 2.NOS.C.9.d
- Massachusetts 2.NBT.B.7
- Michigan 2.NBT.B.7
- Mississippi 2.NBT.7
- Missouri 2.NBT.B.8
- Montana MT.2.NBT.7
- Nebraska 2.N.4.e
- Nevada 2.NBT.B.7
- New Hampshire 2.NBT.B.7
- New Jersey 2.NBT.B.7
- New Mexico 2.NBT.B.7
- New York NY-2.NBT.7.a, NY-2.NBT.7.b
- North Carolina NC.2.NBT.7.a, NC.2.NBT.7.b, NC.2.NBT.7.c, NC.2.NBT.7.d
- Ohio 2.NBT.7
- Oregon 2.NBT.B.7
- Pennsylvania CC.2.1.2.B.3
- Rhode Island 2.NBT.B.7
- South Dakota 2.NBT.B.7
- Tennessee 2.NBT.C.7
- Texas 111.4.b.4.C, 111.4.b.4.D
- Utah 2.NBT.7
- Vermont 2.NBT.B.7
- Washington 2.NBT.B.7
- West Virginia M.2.12
- Wisconsin M.2.NBT.B.7
- Wyoming 2.NBT.7a, 2.NBT.7b, 2.NBT.7c, 2.NBTP.7.A, 2.NBTP.7.B, 2.NBTP.7.C
More in this unit
- Numbers to 1,000 three ways
- What is a digit worth?
- Zero holds the tens place
- Many names for one number
- New names, same number
- Comparing three-digit numbers
- Plot and order on a number line
- Same digits, different places
- Read the line's labels
- Ten more, a hundred more
- Ten more past a hundred
- Subtracting to 1,000
- Subtraction does not turn around
- Trade only when you need to
- Skip-count past a hundred
- Counting by 25s
- Which estimate makes sense?