Rachel has taken 6 tests so far and has received scores of 83%, 92%, 79%, 88%, 89%, and 95%. what must rachel receive on her seven test to have an average score of 90%?

Gregory draws a scale drawing of his room. the scale that he uses is 1 cm : 4 ft. on his drawing, the room is 3 centimeters long. which equation can be used to find the actual length of gregory's room?