Making a decade

randRange(1, 9) randRange(1, 9) 10 - B rand(2)

A * 10 + B + C

\Large{ A * 10 + B + C C + A * 10 + B = ?}

\Large{= \pink{A}\blue{B} + \blue{C}}

\Large{= \pink{A * 10} + \blue{B} + \blue{C}}

\Large{= \blue{C} + \pink{A}\blue{B}}

\Large{= \blue{C} + \pink{A * 10} + \blue{B}}

\Large{= \pink{A * 10} + \blue{B} + \blue{C}}

\Large{= \pink{A * 10} + \blue{B + C}}

\Large{= A * 10 + B + C}

randRange(1, 8) randRange(1, 9) randRange(1, 9 - A) 10 - B

A * 10 + B + C * 10 + D

\Large{A * 10 + B + C * 10 + D = ?}

\Large{= \pink{A}\blue{B} + \pink{C}\blue{D}}

\Large{= \pink{A * 10} + \blue{B} + \pink{C * 10} + \blue{D}}

\Large{= \pink{A * 10} + \pink{C * 10} + \blue{B} + \blue{D}}

\Large{= \pink{A * 10 + C * 10} + \blue{B + D}}

\Large{= A * 10 + C * 10 + B + D}