correct answer is: a) 6 m 6 dcm

Explanation

Here,
The ratio of the circumference and diameter of a circle is 22\;:\;7\;.
And, the length of the diameter of a circle is 2 m 1 dcm.
Or \left(2\times10\right)+1 dcm = 21 dcm _{[1 m = 10 dcm]}
Let, the circumference of the circle is ‘x’ dcm.
According to the question,
22\;:\;7=x\;:\;21
\rightarrow\large\frac{22}{7}\normalsize=\large\frac{x}{21}
\rightarrow 7x=\left(22\times21\right)
\rightarrow x=\large\left(\frac{22\times21}{7}\right)
\rightarrow x=66
\therefore Circumference of the circle is 66 dcm.
Ans: The circle circumference is 66 dcm or 6 m 6 dcm.

Alternative phrasings for this particular math query are:

1. Given a circle’s diameter of 2 meters and 1 decimeter, and a circumference-to-diameter ratio of 22:7, what is the circle’s circumference?
2. If the diameter of a circle measures 2 meters and 1 decimeter, and the ratio of circumference to diameter is 22:7, what is the circumference of the circle?
3. When the diameter of a circle is 2 meters and 1 decimeter, and the ratio of circumference to diameter is 22:7, what is the circle’s circumference?