The question y= 0.25X describes a proportional relationship between x and y. What is the constant proportionality?

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

7. the area of the playing surface at the olympic stadium in beijing isof a hectare. what area will it occupy on a plan drawn to a scaleof 1: 500?

Kristen is wrapping presents for the holidays. she has a box that measures 4 ft. x 2 ft. x 2 ft. how many square feet of wrapping paper does she need to cover the box without overlapping?