Lab 7 Discussion

About Choices

Choice 1- Approach

• Generate problems

• Solve problems entered by students

• Teach students how to work with fractions

Choice 2 – Presentation Format

• Menu

• Required sequence of things to do

Choice 3 -Operations to implement

Addition needs two operands needs common denominator needs to reduce answer needs to know how to addSubtraction needs two operands needs common denominator needs to reduce answerMultiplication need to reduce needs two operandsDivision

need to invert and multiplyneeds two operands

Helper Operations Needed

• common denominator – can get by multiplying two denominators

• least common denominator • swap numerator and denominator

– for division

• reduce (i.e. put in lowest terms) – find common factor of numerator &

denominator – divide each by that common factor

Choice 4 - Interface

• Java options pane

• Text

Problems to address

Denominator entered by student is 0

Number is entered as a mixed number

How will fraction(s) be entered?

Numerator and denominator

String

Terminology

Here is a chart showing words used by students in creating the Fractions design/program and providing alternate words that a public school teacher would have used with her class.

U:\Web\CS239\Lectures\Lecture8\Teacher_Words.htm