A bakery sells chocolate cupcakes and mocha cupcakes. It sold 400 cupcakes in a day, and 68% of them were mocha. How many of the cupcakes sold that day were chocolate?
The number of mocha cupcakes sold was 68/100*400=<<68/100*400=272>>272 cupcakes.
So, 400-272=<<400-272=128>>128 cupcakes sold are chocolate. Answer: \boxed{128}.