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2nd grade math · Unit 3: Adding and subtracting within 100

Add four numbers

What this lesson shows

Four two-digit numbers in a column. Add the tens, then the ones, pairing ones that make 10.

The worked example

The lesson works this one step by step: 23 + 14 + 37 + 16. Then your kid tries one like it on paper.

The steps

  1. Add the tens
  2. Pair ones that make 10
  3. Add the other ones
  4. Put them together

Helping at home

Write the numbers in a column, tens under tens. Add the tens. Then add the ones, first two that make 10. Put the tens and the ones together.

If your kid gets stuck

Find two ones that make 10.

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.

See how Lux works

Standards

  • Common Core 2.NBT.B.6
    Add up to four two-digit numbers using strategies based on place value and properties of operations.
Matches standards in 40 statesSee each state's code

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