In the Math Problem Solving ASA this week we thought about sharing cookies evenly among 9 children, and figured out properties of remainders (les restes) when numbers are added or multiplied. After solving the problems on the worksheet below, we deduced the rule for deciding if a number is divisible by 9, without doing the division.
Having learned how to do this kind of problem fast, we divided into two teams and competed to solve a sequence of speed problems.
