Effectue les calculs suivants :
\[\Eqalign{
(-12)\div6&=\ldots\kern1cm&21\div(-7)&=\ldots\kern1cm&(-30)\div(-5)&=\ldots\cr
(-36)\div(-9)&=\ldots&(-32)\div(-8)&=\ldots&(-18)\div6&=\ldots\cr
(-99)\div9&=\ldots&(-99)\div(-11)&=\ldots&99\div(-9)&=\ldots\cr
(-45)\div(-5)&=\ldots&(-72)\div(-9)&=\ldots&72\div(-8)&=\ldots\cr
27\div(-3)&=\ldots&(-27)\div3&=\ldots&(-27)\div(-3)&=\ldots\cr
35\div(-7)&=\ldots&(-35)\div(-7)&=\ldots&(-35)\div(-5)&=\ldots\cr
}\]