Answer:
Now they have left to decorate 20% cupcakes.
Explanation:
Darren and Latisha are decorating cupcakes for a bake sale.
They need to decorate 100 cupcakes.
Each of them has decorated 40% of the cupcakes = 40% + 40% = 80%
Both of them has decorated 80% of the cupcakes.
80% of 100 cupcakes = 80 cupcakes
Now they have left to decorate 100 - 80 = 20
Now they have left to decorate 20% cupcakes.