A sample analysis of examination results of 500 students was made. It was found that 220 students had failed,170 had secured a third class,90 were placed in second class and 20 obtained first class. Are these figures commensurate with the general examination result? Which is in the ratio of 4:3:2:1 for various categories respectively?(the table for value of x square for 3 degree of freedom at 5% level of significance is 7.81)
