Grade 2Place Value to 1,0002.NBT.A.2

Skip Counting by 5s, 10s and 100s

Count by fives, tens and hundreds within 1,000.

Not started Jump to practice

Skip counting means counting by the same jump each time. You already count by tens (Counting by Tens). Now count by 5s, 10s and 100s, starting from any number up to 1,000.

Counting by 5s: every shaded number ends in 5 or 0.

Why it works

Adding 10 adds one more ten, so only the tens digit goes up by 1. Adding 100 adds one more hundred, so only the hundreds digit goes up. Adding 5 to a number that ends in 0 or 5 makes the ones digit flip: 0, 5, 0, 5.
Ten jumps of 100 reach 1,000.

Worked example: Count by 10s across a hundred

Count by 10s from 470.
  1. 470, 480, 490: only the tens digit changes.
  2. 10 more than 490 makes 10 tens, which is a new hundred.
  3. So the next numbers are 500, 510, 520.

Answer: 470, 480, 490, 500, 510, 520

Worked example: Count by 100s

Count by 100s from 160.
  1. Only the hundreds digit changes.
  2. 160, 260, 360, 460, 560.

Answer: 160, 260, 360, 460, 560

Worked example: Count by 5s

Count by 5s from 35.
  1. The ones digit goes 5, 0, 5, 0.
  2. 35, 40, 45, 50, 55, 60.

Answer: 35, 40, 45, 50, 55, 60

Key idea

Skip counting adds the same amount each time. Counting by 10s changes the tens digit; counting by 100s changes the hundreds digit.

Common mistake

After 490, writing “4100.” The tens place can’t hold 10. When the tens reach 10, they make a new hundred: $490 + 10 = 500$.
Grown-up tip: Count nickels by 5s and dimes by 10s, or count by 100s as you climb the stairs.

Practice

Pass with 3 right answers, the last 2 in a row. Each right answer earns 1 XP.

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Builds on

Leads to

Sources and further reading

  • Common Core State Standards for Mathematics, Grade 2, standard 2.NBT.A.2 (count within 1000; skip-count by 5s, 10s and 100s)
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