Page 42 - NUMINO Challenge_D2

Problem solving Key Points

1 There are 10 cars. Daniel has 10 different car In the worst case,
keys and wants to unlock all 10 cars. At least Daniel needs to try
how many times does he need to try in order to 10 times in order to
unlock all 10 cars? unlock the first door.

2 Ann, Tom, and Mike are the candidates for the The worst case would
class president. The following table shows the be sharing the uncast
number of votes each student received so far. votes between Tom,
who got the most
Candidate Ann Tom Mike votes so far, and
14 17 11 Mike, who got the
Number least votes.
of Votes

The candidate who receives the most votes
becomes the class president. At least how many
more votes does Mike need to get in order to be
the class president? (55 students voted, and
there were 2 invalid votes.)

39Reasoning