The thickness of a Xinhua dictionary is about 5 cm. The thickness of a dictionary is usually a few centimeters, and it can't be thinner, nor can it reach a few centimeters thick. Generally speaking, a book cannot be equal to 6 decimeters or 6 centimeters, so the thickness of a math book is about 6 millimeters. ?

1 The thickness of the book mainly depends on the thickness of the number of pages and the number of pages on the paper. If the number of pages is small and the pages are thin, the thickness of the whole book is not much. The average 100 page book is about 2 cm thick. If the pages are thick, the thickness of the whole book will be relatively thick. So the thickness of a book mainly depends on the number of pages read and the thickness of the paper.

Length unit knowledge point

1. A ruler is a tool for measuring the length of an object. Commonly used length units are: meters and centimeters. The index finger is about 1 cm wide and the arms are about 1 m. 1m = 100cm 100cm = 1m。

2. The measurement unit of shorter objects is usually centimeters, and the measurement unit of longer objects is usually meters.

3. When measuring the length of the object: aim the "0" scale of the ruler at the left end of the object, and then see how many centimeters the right end faces the scale. Object length = large number-decimal number, for example, from scale "0" to scale "6" is 6 cm (6-0=6), and from scale "6" to scale "9" is 3 cm (9-6 = 3); You can also calculate the length of an object by counting.