Solving a percent mixture problem using a linear equation Espai

in the lab, Donna has two solutions that contain alcohol and is mixing them with each other. Solution A is 7% alcohol and Solution B is 2% alcohol. She uses

400 mililiters of Solution A. How many milliliters of Solution B does she use, if the resulting mixture is a 4% alcohol solution?

The boiling point of water at an elevation of 0 feet is 212 degrees fahrenheit (°f). for every 1,000 feet of increase in elevation, the boiling point of water decreases by about 2°f. which of the following represents this relationship if b is the boiling point of water at an elevation of e thousand feet? a) e = 2b - 212 b) b = 2e - 212 c) e = -2b + 212 d) b = -2e + 212