一除法算式,如除数扩大三倍,则商3余2.如被除数扩大11倍,则商78余9.这个除法算式的正确结果是商几余几
问题描述:
一除法算式,如除数扩大三倍,则商3余2.如被除数扩大11倍,则商78余9.这个除法算式的正确结果是商几余几
答
被除数x除数y
(x-2)/3y=3 => x-2=9y=>x=9y+2
(11x-9)/y=78 => 11x-9=78y
有上述推的=> 11(9y+2)-9=78y=> 99y+22-9-78y=0 => 21y=-13 =>y=-13/21x=-25/7