standard_description: Multiply one-digit whole numbers by multiples of 10 in the range 10–90 (e.g., 9 × 80, 5 × 60) using strategies based on place value and properties of operations.
problem_activity: Problem 1
Find the following products.
a.   20 × 4
b.   9 × 300
c.   5 × 6,000
Problem 2
Estimate the following products.
a.   8 × 84
b.   458 × 4
c.   2 × 9,340


aligns: no