Monday
Monday: Common denominators
Riley the Raccoon spreads his puzzle pieces on a flat stump, his lantern glowing beside him.
"This puzzle board has two painted strips," he says.
"One strip covers 1/2 of the board. The other covers 1/3."
"How much of the board is painted?" Bennie the Bear lays the strips side by side.
"Halves and thirds are different sizes," he says. "They do not line up."
Riley twitches his striped tail and grins.
"Then let us cut both into smaller pieces that are the same size," he says.
Learn it: equivalent fractions
Cut each half into 3 equal pieces. Now the strip shows 3/6.
Cut each third into 2 equal pieces. Now that strip shows 2/6.
So 1/2 = 3/6 and 1/3 = 2/6. Both now use sixths.
To make an equivalent fraction, multiply the numerator and the denominator by the same number.
1/2 = (1 × 3)/(2 × 3) = 3/6.
A common denominator is a multiple of both denominators. 6 is a multiple of 2 and of 3.
- Read the question.
- Tap your answer.
- Read the question.
- Tap your answer.
- Read the question.
- Tap your answer.
- Write each one in sixths if it helps.
- Tap them from least to greatest.
| Sentence | True or false? |
|---|---|
| 1/2 = 3/6 | ? |
| 2/3 = 4/6 | ? |
| 1/4 = 2/12 | ? |
| 3/5 = 6/10 | ? |
Fold one strip in half, and another into fourths.
Fold the last strip into eighths: in half, in half again, and in half again.
Line them up. How many eighths match one half? How many match one fourth?
Fine work! Tomorrow Riley adds fractions with different denominators.