randRange(1, 9) randRange(2, 9) randRange(1, B - 1)
A * 10 + B - C

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

`\Large{= \pink{A}\blue{B} - \blue{C}}`

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

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

`\Large{= \pink{A}\blue{B - C}}`

randRange(2, 9) randRange(1, 9) randRange(1, A - 1)
A * 10 + B - C * 10

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

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

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

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

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

`\Large{= \pink{A - C}\blue{B}}`