Answer:
150 m
Step-by-step explanation:
Total distance walked
= perimeter of the garden
= 42 + 42 + length of arc
[tex] = 84 + \frac{ \theta}{360 \degree} \times 2\pi \: r \\ \\ = 84 + \frac{90 \degree}{360 \degree} \times 2 \times \frac{22}{7} \times 42 \\ \\ = 84 + \frac{1}{4} \times 44 \times 6 \\ \\ = 84 + 11 \times 6 \\ \\ = 84 + 66 \\ \\ = 150 \: m[/tex]