Question

fimd the circumference for a circle pi = 3.142 diameter= 20cm

Answer 1

2×3.142×10=62.84cm is correct

Answer 2

$circumference = 2\pi \: r \\ = 2 \times 3.142 \times 10 \\ = 2 \times \frac{3142}{1000} \times 10 \\ = 2 \times 31.42 \\ = 62.84cm$