Find the echelon form of this augmented matrix

For the equations below which statement is true ?

Last year, a state university received 3,560 applications from boys. of those applications, 35 percent were from boys who lived in other states. part a)how many applications did the university receive from boys who lived in other states? part b)applications to the university from boys represented 40percent of all applications. how many applications did the university receive in all? i don't how to do part b so me and plz tell how you got your answer

In the sixth grade 13 out of 20 students have a dog if there are 152 sixth grade students how many of them have a dog