The dental health examination of grade one and grade six students in Lianhua Primary School is as follows.

In the title, "the proportion of sixth-grade students suffering from caries is 3: 1" should be "the proportion of sixth-grade students suffering from caries is 3: 1". If it is the ratio of the number of sixth-grade students suffering from dental caries and there is no solution, then the equation is 130+59+x+3=(59+x+3)X3.