Uh-oh, it looks like your Internet Explorer is out of date.

For a better shopping experience, please upgrade now.

Ratio and Proportion

Ratio and Proportion

by Marion Smoothey

Editorial Reviews

School Library Journal - School Library Journal
Gr 4-6Three fatally flawed offerings. There seems to have been no communication between the author and illustrator: the text often asks readers to get information from the pictures that Baum doesn't provide. Also, Smoothey keeps suggesting games, but doesn't explain their rules. Then there are the indexeshalf of the entries refer to the subject matter of word problems instead of the concepts and methods supposedly being taught. Calculators presents a brief history of the topic as well as instructions on how to use a variety of relatively unsophisticated machines. This gives it a wide range of possible errors. It also has a drawing of a slide rule that could be used for a ``how many mistakes can you find?'' game, a typo that gives a set of six simultaneous equations seven unknowns, and numerous misleading oversimplifications. Worse, it ignores the standard rules about order of operations. Estimating attempts and achieves less. It suffers from drawings that don't show what the author intended, and doesn't explain rounding or make clear the meaning of significant figures. A section on estimating costs of meals ignores real-life complications such as sales tax and a tip. Ratio and Proportion attempts the least, spending many pages on pictures of groups to determine proportions of tables to chairs or lions to lionesses to lion cub, then more pages to show the answers. Thereby it keeps its error count lower, but not as low as it should be. It never establishes a relationship between ratio and division, which leads to 2:5 being equated with 2 1/2. These volumes are reasonably appealing to look at; with detailed editing and proofreading, they could have been as good as they look. As they stand, math teachers will thank you not to let kids see them.Margaret Chatham, formerly at Smithtown Library, NY

Product Details

Cavendish, Marshall Corporation
Publication date:
Let's Investigate Series
Product dimensions:
8.43(w) x 10.36(h) x 0.48(d)
Age Range:
9 - 13 Years

Customer Reviews

Average Review:

Post to your social network


Most Helpful Customer Reviews

See all customer reviews