Question

How many decimetres are there in 15 centimetres?
A.150 dm
B.1.5 dm
C.0.15 dm
D.None of these

Answer 1

The decimetres unit number 0.10 dm converts to 1 cm, one centimetre. It is the equals length value of 1 centimetre but in the decimetre’s length unit alternative. One decimetre (dm) = 10 centimetres (cm)

Complete step by step answer:
A decimetre (dm) is a unit of length in the metric system. The term “Deci” means one-tenth, and so decimetre means one-tenth of a meter. The symbol used to write decimetre is dm.
A centimetre (cm) is a decimal fraction of the base SI unit of length, the meter, which is defined as the length of the path travelled by the light in vacuum during a time interval of $\dfrac{1}{{299,792,458}}$ of a second. It is a metric unit of measurement used for measuring the length of an object. It is written as cm.
We know, $1cm = 0.10dm$
$15cm = 0.10 \times 15 = 1.5dm$

The correct answer is option (B).

Note: In geometric measurements, length most commonly refers to the longest dimension of an object. The term “length” is reserved for a certain dimension of an object along which the length is measured. Several units are used to measure length. In the International System of Units (SI), the basic unit of length is the meter, which is defined in terms of the speed of light. The meter is defined as the length of the path travelled by light in vacuum during a time interval of $\dfrac{1}{{299,792,458}}$ of a second. There are many other commonly used units of length such as the inch, the foot, the yard, and the mile.