standard_description: Fluently add and subtract within 20 using mental strategies. (See standard 1.OA.6 for a list of mental strategies.) By end of Grade 2, know from memory all sums of two one-digit numbers.
problem_activity: Round each of the following numbers to the nearest ten. Show or explain your thinking.
a.
$$46 \approx$$
__________
b.
$$24 \approx$$
__________


aligns: no