This is math and what is this answer me what is (-21)+(-9)

For a read-a-thon, jay and odhràn each started reading a book at the same time and continued reading for several hours. jay's book had 278 pages, and he read 55 pages per hour. odhràn's book had 238 pages, and he read 45 pages per hour. after how many hours did they have the same number of pages left, and how many pages were left?

Adiverr from the university of florida women’s swimming and diving team is competing in the ncaa zone b championships

The pyramid below was dissected by a horizontal plane which shape describes the pyramid horizontal cross section