fraction product sequence

a ppt is here

it's best not to cancel down, to appreciate a pattern

a proof by pulling it out (induction-wise)

unit fraction probability

from a problem posed by David Wells

a ppt is here

possibly of more interest as a context for multiplying fractions (involving cancelling) than combined event probability (without replacement)

note that a particular subset of the unitary fractions: 1/4, 1/9, 1/16 ...
are impossible to achieve

fractions practice makes perfect

a ppt is here

multiplying mixed numbers

sum one

fraction reduction

fraction multiplication with cancelling

there are variants for many of these, some with three overall (as in the example above)

fraction multiplication pictures

using diagrams to show a fraction multiplication result seems helpful
because it fits with other uses of an 'area' model for multiplication
and seems effective in terms of conveying some rationale for the process

however, there are a few weeny complications with it

what do these fraction multiplication pictures show?















technically, a fraction of a length multiplied by a fraction of a different length is a fraction of the area of a rectangle, so for the first picture:

to a certain extent the complication is simplified by having fractions of unit lengths (in a unit square, making L = 1 and W = 1 and so LW = 1)

this is an approach taken by the helpful:
nzmaths.co.nz
learning objects
fractions of fractions tool

fraction multiplication (2)

this is an approach advocated by Caleb Gattegno to provide some justification for the technique for multiplying fractions

fraction multiplication (1)