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A mixing problem Painter Joe needs to complete a job that requires 50 gallons of brown paint and 50 gallons of gray paint. The required shades of brown and gray can be obtained by mixing the primary colors (red, yellow, and blue) in the proportions given in the following table. The same shades can be obtained by mixing secondary colors (orange, green, and purple), each of which is based on mixing two out of three primary colors in equal proportions (red/yellow for orange, yellow/blue for green, and red/blue for purple). A mixing problem Painter Joe needs to complete a job that requires 50 gallons of brown paint and 50 gallons of gray paint. The required shades of brown and gray can be obtained by mixing the primary colors (red, yellow, and blue) in the proportions given in the following table. The same shades can be obtained by mixing secondary colors (orange, green, and purple), each of which is based on mixing two out of three primary colors in equal proportions (red/yellow for orange, yellow/blue for green, and red/blue for purple)