standard_description: Add and subtract within 1000, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method. Understand that in adding or subtracting three-digit numbers, one adds or subtracts hundreds and hundreds, tens and tens, ones and ones; and sometimes it is necessary to compose or decompose tens or hundreds.
problem_activity: Problem 1
Solve.
a.
$$380\div10=$$
________
b.
$$4,820 \times \frac{1}{10}=$$
________
Problem 2
Explain what happened to the value of the 8 in both problems in #1.


aligns: no