color(blue)("Important fact 1")Important fact 1
Multiply by 1 and you do not change the value. However 1 comes in many forms. So you can change a the way a fraction looks without changing its actual value.
color(blue)("Important fact 2")Important fact 2
A fraction consists of ("count")/("size indicator") -> ("numerator")/("denominator")countsize indicator→numeratordenominator
You can not directly add or subtract the counts unless the size indicators are the same
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" "color(green)(=[2/5color(red)(xx1)] color(white)(.)" "+" "[1/5color(red)(xx1)]" "-" "3/10 =[25×1]. + [15×1] − 310
color(white)(..)color(green)(=[2/5color(red)(xx2/2)]" " +" "[1/5color(red)(xx2/2)]" "-" "3/10..=[25×22] + [15×22] − 310
color(white)(.)" "=[4/10 ]color(white)(...)" "+" "color(white)(...)[2/10]" "-" "3/10
" "=6/10" "-" "3/10
" " =(6-3)/10
" " = 3/10
color(white)(.)
