Can any1 help me with this please ?

Empty box + box + empty box fill in the box is equal to 30 how

Jenisey has $24 to spend on seven pencils. after buying them she had $10. how much did each pencil cost.?

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