Estimating and Assessing the Reasonableness of Multiplying Fractions

This lesson teaches how to assess the reasonableness of a product by estimating. It explains how to determine which whole number a fraction is closest to and use that for estimation. Several examples are provided, including multiplying 2 by 3/4, 3 by 5/3, 5 by 4/5, and 2 by 18/10. The lesson emphasizes using number lines and visual models to understand the estimation process and verify the reasonableness of the calculated product.

Explain how to use a number line to assess the reasonableness of a product.

What conclusion can we draw about the reasonableness of the answer 3 and 6/10 for the product of 2 times 18/10?