PLEASE HELP WITH THIS PROBLEM

Two customers went to a post office. first customer paid $12 for 14 and 5 envelopes the second paid 24.80 for 10 postcards and 15 envelopes. what is cost of each envelope?

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?

Jordan has $5.37, which he is using to buy ingredients to make salsa. he is buying one red pepper for $1.29 and three pounds of tomatoes. if jordan has exactly the right amount of money he needs, what is the price per pound of the tomatoes? choose the correct equation to represent this real-world problem. solve the equation and verify the reasonableness of your answer. a pound of tomatoes costs .