Wednesday
Wednesday: Powers of 10
Bennie the Bear brings a crate of apples to the meadow.
"This crate holds 10 bags, and each bag holds 10 apples," he says.
Rosie the Rabbit counts. "Ten bags of ten is 100 apples!"
"Now picture 10 crates like this one," says Bennie.
Rosie thinks hard. "That is 10 × 10 × 10, which is 1,000 apples."
"Numbers like 10, 100 and 1,000 are powers of 10," says Bennie.
"When we multiply by them, the zeros make a pattern we can see."
Rosie claps. "I love patterns!"
Learn it: powers of 10 and exponents
10 × 10 = 100. We call this 10 to the 2nd power.
10 × 10 × 10 = 1,000. We call this 10 to the 3rd power.
The 3 is the exponent. It tells how many tens we multiply.
10 to the 3rd power has 3 zeros: 1,000.
Learn it: the zeros pattern
45 × 10 = 450. Each digit moves one place to the left.
45 × 100 = 4,500. Each digit moves two places.
45 × 1,000 = 45,000. Each digit moves three places.
The number of zeros in the power of 10 tells how many places the digits move.
- Read the question.
- Tap your answer.
- Read the question.
- Tap your answer.
- Read the question.
- Tap your answer.
| Sentence | True or false? |
|---|---|
| 25 × 100 = 2,500 | ? |
| 25 × 1,000 = 2,500 | ? |
| 10 × 10 × 10 = 1,000 | ? |
| 300 × 10 = 30,000 | ? |
- Think about how Bennie multiplies.
- Tap the steps in order.
How many things would 10 packs hold? How about 100 packs?
Write each answer as a multiplication sentence.
Look at the zeros. What pattern do you see?
Super patterns! Tomorrow Chris tells a story about decimals and powers of 10.