Idea 2of 24Builds onEqual parts make a fraction
Top number, bottom number
What does each number in a fraction tell you?
Today you'll discover
- what the bottom number counts
- what the top number counts
- how to name the part that is left
Think firstA strip in equal parts, some shaded
What fraction of the strip is shaded?
Decide first, then press Next. Count all the parts, then the shaded ones.
A strip cut into five equal parts with three shaded. The parts are numbered, then the fraction is written at the right, then a strip of eight parts with five shaded. The last step shows a pan of six pieces with two shaded.
See the whole ideathe big idea and the key word, in one place
The big idea
The denominator counts the equal parts in the whole; the numerator counts the parts taken.
Compare themNumerator: on top, counts the parts taken. Denominator: on the bottom, counts the equal parts the whole is cut into.
Easy to get wrongThe bottom number counts ALL the parts, shaded or not. 3 shaded and 2 not shaded is 3/5, not 3/2.
Key words
- numerator
- the top number of a fraction: how many equal parts are taken
- denominator
- the bottom number of a fraction: how many equal parts make the whole
Ready to use it?
- Name the fraction a shaded picture shows.
- Say what the numerator and the denominator count.