Answer: Suzy finish frosting the cupcake at 3:22 P.M.
Explanation:
She started at 2:40 p.M. it took her 9 minutes to mix the batter. After mixing the batter, the time would be
2:40 + 0:09 = 2:49 P.M.
It took her 18 minutes to bake the cupcakes. After baking the cupcakes, the time would be
2:49 + 0:18 = 3:07 PM.
It took 5 minutes to let them cool. After cooling them, the time would be
3:07 + 5 = 3:12 PM.
It took her 10 minutes to frost the cupcakes. Therefore, after frosting the cupcakes, the time would be
3:12 + 0:10 = 3:22 P.M.