Question

How do you subtract `4\frac { 3} { 4} - 2\frac { 1} { 5}`?

Answer 1

This is another way of doing it

`4 3/4-2 1/5" "=" "2 11/20`

Explanation:

`color(blue)("Calculating the different parts - and explaining")`

`color(brown)("Whole numbers parts first")`

`4-2=2`

`color(brown)("Fraction parts next")`

A fractions construct is `("count")/("size indicator")->("numerator")/("denominator")`

You can not DIRECTLTY add or subtract the 'counts' unless the 'size indicators' are the same

Multiply by 1 and you do not change the intrinsic value. However, 1 comes in many forms so you can change the way a number looks without changing its intrinsic value.

`color(green)([3/4color(red)(xx1)] -[1/5color(red)(xx1)]`

`color(green)([3/4color(red)(xx5/5)] -[1/5color(red)(xx4/4)]`

`color(green)([15/20]-[4/20] " "=" "+11/20`
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
`color(blue)("Putting it all together")`

`4 3/4-2 1/5" "=" "2+11/20" "=" "2 11/20`