Tuesday
Tuesday: Expanded form
Chris the Coyote sits on a log with his notebook open.
"A good story has parts," he says. "A beginning, a middle and an end."
Bennie the Bear writes 3.472 on a flat stone.
"Numbers have parts too," says Bennie. "We can show each part by itself."
He writes 3 + 0.4 + 0.07 + 0.002 under the number.
Chris counts the parts. "Three ones, four tenths, seven hundredths and two thousandths!"
"Put the parts back together, and you get the whole number again," says Bennie.
Learn it: break a decimal into its places
With decimals: 3.472 = 3 + 0.4 + 0.07 + 0.002.
With fractions, each digit is multiplied by the value of its place.
3.472 = 3 × 1 + 4 × (1/10) + 7 × (1/100) + 2 × (1/1000).
Both ways show what each digit is worth.
A zero digit adds nothing, so we can leave it out.
- Read the question.
- Tap your answer.
- Read the question.
- Tap your answer.
- Read the question.
- Tap your answer.
- Read the question.
- Tap your answer.
| Sentence | True or false? |
|---|---|
| 5 + 0.2 + 0.03 = 5.23 | ? |
| 1 + 0.6 + 0.004 = 1.64 | ? |
| 3 × (1/10) + 1 × (1/100) = 0.31 | ? |
| 8 + 0.05 = 8.5 | ? |
Fold the paper so each digit is on its own section.
Under each digit, write what it is worth.
Add the parts to check that you get your number back.
Nice work! Tomorrow we compare and order decimals.