Question

find the diameter of the circle whose circumference is 77cm​

Answer 1

Answer:

$2\pi r \: = 77 \\ \\ = \geqslant 2 \times \frac{22}{7} \times r = 77 \\ \\ = \geqslant 44r = 77 \times 7 \\ \\ = \geqslant r = \frac{77 \times 7}{22} \\ \\ = \geqslant \: r = \frac{49}{2} units \\ \\ = \geqslant d = 2 \times r \\ \\ = \geqslant d = 2 \times \frac{49}{2} \\ \\ = \geqslant d = 49$