An example: Math Drill

Press , , , then to start 25 additions. The first question appears: $\displaystyle 14 + 7$. Type 21 and press . A check mark appears: the answer is Correct, and the next question comes: $\displaystyle 9 + 16$. Give a wrong answer: type 24 and press . A cross appears: the answer is Wrong, and the same question comes again. Type 25 and press : Correct. The next question is $\displaystyle 8 + 5$. This time press without an answer: the calculator shows the right answer, 13, and counts it as wrong. The calculator chooses the questions at random, so yours will be different.

▶ Watch this step in the video (2:01:02)