Download In “What`s My Rule?” problems, there is a diagram that represents an

What’s My Rule
In “What’s My Rule?” problems, there is a diagram that
represents an imaginary “function machine.” The machine
takes in a number, applies a rule, and puts out a new number.
A table is used to keep track of “in” and “out” numbers.
To solve a “What’s My Rule?” problem, some missing
information (the “in” numbers, the “out” numbers, or the
rule) must be found by using the information that is already
given.
Information from the Home Connection Book of the Everyday Math Program
Created by: Chris Cheatham and Maria Farmer WB 2010
Finding the rule
The function machine starts by having all of
the “in” and “out” columns filled in on the
table. The students must use that
information to help them determine what
the rule is for the function machine.
Start by picking one row with completed
“in” and “out” numbers.
Then you first need to determine if the the
number in the “out” column is bigger or
smaller than the number in the “in” column.
Last you need to start at the number in the
“in” column and count until you get to the
number out column, and record the number
of hops that it took.
Created by: Chris Cheatham and Maria Farmer WB 2010
Finding the “out” numbers
To figure out what number
goes in the “out” column
you must start with the
number in the “in” column.
Then apply the rule from
the rule box to that number.
That will give you the
number for the “out“ box.
Created by: Chris Cheatham and Maria Farmer WB 2010
Finding the “in” numbers
Some children like to find
the “in” number by viewing
the problem as:
?-3=7
Other students prefer to
reverse the rule in the rule
box to help them solve the
problem. If the rule is -3 the
students would use
7+3=_____ as their problem.
Created by: Chris Cheatham and Maria Farmer WB 2010