Answer:
[tex]\frac{1}{3}[/tex] of the doughnuts in the box have frosting and sprinkles.
Step-by-step explanation:
If there are [tex]x[/tex] doughnuts in the box. Then, [tex]\frac{2}{3} \times x = \frac{2x}{3}[/tex] of the doughnuts in the box have frosting. Therefore, [tex]\frac{1}{2} \times \frac{2x}{3} = \frac{1}{3}x[/tex] of the doughnuts with frosting have sprinkles. This implies that [tex]\frac{1}{3}[/tex] of the doughnuts in the box have frosting and sprinkles.